SLG


Line plots across dimensions of each concept
Line plots across concepts
Tables

Table of contents



us-gaap:CommonStockValue
us-gaap:StatementEquityComponents
us-gaap:SharesOutstanding

us-gaap:CommonStockSharesIssued

us-gaap:CommonStockSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareDiluted
us-gaap:AwardType
us-gaap:AllocatedShareBasedCompensationExpense
us-gaap:AwardType, us-gaap:PlanName
us-gaap:PlanName

us-gaap:ComprehensiveIncomeNetOfTax
us-gaap:ConsolidatedEntities

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest
us-gaap:ConsolidatedEntities

us-gaap:CostsAndExpenses
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:GainsLossesOnExtinguishmentOfDebt

us-gaap:IncomeTaxExpenseBenefit

us-gaap:InterestExpense
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:InterestIncomeExpenseNet

us-gaap:InterestIncomeOperating

us-gaap:NetIncomeLoss
us-gaap:ConsolidatedEntities

us-gaap:NetIncomeLossAttributableToNoncontrollingInterest

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted
us-gaap:ConsolidatedEntities

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax
us-gaap:ConsolidatedEntities

us-gaap:OtherComprehensiveIncomeLossNetOfTax
us-gaap:ConsolidatedEntities

us-gaap:OtherIncome
us-gaap:ConsolidatedEntities

us-gaap:ProfitLoss
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:ProductOrService, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax

us-gaap:Revenues
us-gaap:ConsolidatedEntities
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:SellingGeneralAndAdministrativeExpense
us-gaap:ConsolidatedEntities

us-gaap:Assets
us-gaap:ConsolidatedEntities
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:Liabilities
us-gaap:ConsolidatedEntities

us-gaap:LiabilitiesAndStockholdersEquity
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:StockholdersEquity

us-gaap:CashAndCashEquivalentsAtCarryingValue
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents
us-gaap:ConsolidatedEntities

us-gaap:Land
slg:InvestmentsByConsolidatedAndNonconsolidatedEntities
slg:InvestmentsByConsolidatedAndNonconsolidatedEntities, us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities

us-gaap:FiniteLivedIntangibleAssetsNet

us-gaap:OperatingLeaseRightOfUseAsset
us-gaap:ConsolidatedEntities

us-gaap:OtherAssets
slg:InvestmentsByConsolidatedAndNonconsolidatedEntities
slg:InvestmentsByConsolidatedAndNonconsolidatedEntities, us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:LongTermDebt
us-gaap:DebtInstrument
us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive

us-gaap:OperatingLeaseLiability
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:StockholdersEquity

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RelatedPartyTransactionsByRelatedParty, us-gaap:StatementEquityComponents
us-gaap:StatementClassOfStock, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

us-gaap:CommonStockValue

us-gaap:AdditionalPaidInCapital

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax
us-gaap:ConsolidatedEntities

us-gaap:TreasuryStockValue

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

us-gaap:NetCashProvidedByUsedInOperatingActivities
us-gaap:ConsolidatedEntities

us-gaap:NetCashProvidedByUsedInInvestingActivities
us-gaap:ConsolidatedEntities

us-gaap:NetCashProvidedByUsedInFinancingActivities
us-gaap:ConsolidatedEntities

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect
us-gaap:ConsolidatedEntities

us-gaap:AmortizationOfFinancingCosts
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:DepreciationDepletionAndAmortization
us-gaap:ConsolidatedEntities

us-gaap:IncreaseDecreaseInAccountsReceivable
us-gaap:ConsolidatedEntities

us-gaap:NetCashProvidedByUsedInOperatingActivities
us-gaap:ConsolidatedEntities

us-gaap:NetIncomeLoss
us-gaap:ConsolidatedEntities

us-gaap:ProfitLoss
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:NetCashProvidedByUsedInInvestingActivities
us-gaap:ConsolidatedEntities
us-gaap:BusinessAcquisition, us-gaap:SubsequentEventType
us-gaap:PaymentsToAcquireRealEstate

us-gaap:PaymentsToAcquireInvestments
us-gaap:ConsolidatedEntities

us-gaap:NetCashProvidedByUsedInFinancingActivities
us-gaap:ConsolidatedEntities

us-gaap:PaymentsOfDividends
us-gaap:ConsolidatedEntities

us-gaap:PaymentsForRepurchaseOfCommonStock
us-gaap:ConsolidatedEntities
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice

slg:CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonthsIntoEquityInNetIncome
slg:DividendType, us-gaap:StatementEquityComponents
slg:CommonStockDividendsPerShareStockPaid

slg:ConsolidationOfJointVentureInterest
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

slg:ConsolidationOfRealEstateInvestment
us-gaap:ConsolidatedEntities

slg:DebtAndEquitySecuritiesCreditLossExpenseReversal

slg:DebtAndPreferredEquityReserves
us-gaap:ConsolidatedEntities

slg:DeferredCompensationPlanAndStockAwardNet
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents
us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents
slg:DeferredCompensationPlanAndStockAwardShares
us-gaap:StatementEquityComponents

slg:DeferredLoanCostsAndCapitalizedLeaseObligation
us-gaap:ConsolidatedEntities

slg:DepreciableRealEstateReservesAndImpairment
us-gaap:ConsolidatedEntities

slg:DistributedEarningsDiluted
us-gaap:ConsolidatedEntities

slg:DistributionToNoncontrollingInterestOperatingPartnership
us-gaap:ConsolidatedEntities
slg:DistributionsPreferredUnits
us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents

slg:DistributionsToNoncontrollingInterestsOtherPartnerships
us-gaap:ConsolidatedEntities
us-gaap:StatementGeographical
slg:EquityMethodInvestmentsOwnershipPercentageAcquired
us-gaap:StatementGeographical
slg:EquityMethodInvestmentsOwnershipPercentageIncreaseDecrease

slg:ExtinguishmentOfDebtInConnectionWithPropertyDispositions
us-gaap:ConsolidatedEntities

slg:FinanceLeaseCost

slg:FinanceLeaseInterestExpenseBeforeCapitalizedInterest

slg:FinanceLeaseInterestExpenseCapitalized

slg:FinancingReceivableAllowanceForCreditLossesWriteOffsAndReclassifications

slg:IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

slg:IncreaseDecreaseInAccruedLiabilitiesAndOther
us-gaap:ConsolidatedEntities

slg:IncreaseDecreaseInOperatingLeaseLiability
us-gaap:ConsolidatedEntities

slg:IncrementalCommonSharesAttributableToRedemptionOfUnitsToCommonShares
us-gaap:ConsolidatedEntities
slg:IncrementalCommonUnitsAttributableToDilutiveEffectOfNonvestedSharesWithForfeitableDividends
us-gaap:ConsolidatedEntities
slg:IncrementalCommonUnitsAttributabletoSharebasedPaymentArrangements

slg:InterestExpenseNet
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty

slg:IssuanceOfSpecialDividendStockDividend
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities
slg:MinorityInterestIncreaseDecreaseFromFairValueAdjustment
us-gaap:ConsolidatedEntities
slg:NetIncomeLossAllocatedToCommonUnitholders

slg:NetIncomeLossAvailableToCommonStockholdersAfterDistributedAndUndistributedEarningsAllocationBasic
us-gaap:ConsolidatedEntities

slg:NonCashLeaseExpense
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities, us-gaap:StatementClassOfStock
slg:NoncontrollingInterestAccruedDividendsOnPreferredUnits
us-gaap:ConsolidatedEntities, us-gaap:StatementClassOfStock
slg:NoncontrollingInterestDecreaseFromDistributionOnPreferredUnits
us-gaap:ConsolidatedEntities
slg:NoncontrollingInterestDecreasefromDistributionstoOtherNoncontrollingInterestHolders

slg:OperatingLeaseCostBeforeCapitalizedOperatingLeaseCosts

slg:OperatingLeaseCostCapitalized

slg:OperatingLeaseLeaseIncomeFixedAndVariableLeasePayments

slg:OperatingPartnershipNoncontrollingInterestFairValueAdjustment
us-gaap:ConsolidatedEntities

slg:OriginationOfDebtAndPreferredEquityInvestments
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities
slg:OtherComprehensiveIncomeLossNetofTaxLessPortionAttributabletoNoncontrollingInterest
us-gaap:ConsolidatedEntities, us-gaap:StatementEquityComponents
us-gaap:ConsolidatedEntities
slg:PartnersCapitalAccountValueUnitDividend
us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents

slg:PaymentsForProceedsFromOtherInvestments
us-gaap:ConsolidatedEntities

slg:PaymentsForRepurchaseOfPartnershipUnits
us-gaap:ConsolidatedEntities

slg:PaymentsToAcquireLandBuildingsAndImprovements
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities, us-gaap:StatementClassOfStock
slg:PreferredStockConvertibleConversionRatio

slg:ProceedsFromConsolidationOfRealEstateInvestment
us-gaap:ConsolidatedEntities

slg:ProceedsFromEquityMethodInvestmentDividendsOrDistributions
us-gaap:ConsolidatedEntities

slg:ProceedsFromNoncontrollingInterestsInOtherPartnerships
us-gaap:ConsolidatedEntities

slg:ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships
us-gaap:StatementEquityComponents
us-gaap:ConsolidatedEntities
slg:ProfitLossLessPreferredDistributions
us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents
us-gaap:ConsolidatedEntities, us-gaap:StatementEquityComponents

slg:PurchasePriceFairValueAdjustmentGainLoss
us-gaap:ConsolidatedEntities

slg:PurchasePriceFairValueAdjustmentGross
us-gaap:ConsolidatedEntities

slg:ReallocationofNoncontrollingInterestInOperatingPartnershipIncreaseDecrease
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

slg:RemovalofFullyDepreciatedRealEstateAssets
us-gaap:ConsolidatedEntities

slg:RentalRevenueIncreaseDecreaseAcquiredLeaseAmortization

slg:RepaymentsOrRedemptionOfDebtAndPreferredEquityInvestments
us-gaap:ConsolidatedEntities

slg:ReversalOfAssetsHeldForSale
us-gaap:ConsolidatedEntities

slg:SECSchedule1229RealEstateCompaniesInvestmentInMortgageLoansOnRealEstateLoanLossReservePeriodIncreaseDecrease

slg:SellerFinancedPurchases
us-gaap:ConsolidatedEntities
us-gaap:AwardType
slg:ShareBasedCompensationArrangementByShareBasedPaymentAwardGrantsInPeriodFairValue

slg:ShareRepurchasesPayable
us-gaap:ConsolidatedEntities

slg:TotalCostsAndExpensesIncludingNonoperatingIncomeExpense
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty

slg:TransactionRelatedCosts
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents
slg:UnitDividendsUnits
us-gaap:ConsolidatedEntities
slg:WeightedAverageNumberofUnitsOutstandingDiluted

srt:MortgageLoansOnRealEstateInterestRate
us-gaap:MortgageLoansOnRealEstateLoanType

us-gaap:AffiliateCosts
us-gaap:ConsolidatedEntities

us-gaap:AmortizationOfAboveAndBelowMarketLeases
us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
us-gaap:AssetImpairmentCharges
us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations, us-gaap:SubsequentEventType
us-gaap:StatementGeographical
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:AssetsFairValueAdjustment
us-gaap:FinancialInstrument
us-gaap:AvailableForSaleDebtSecuritiesGrossUnrealizedLoss

us-gaap:CapitalExpendituresIncurredButNotYetPaid
us-gaap:ConsolidatedEntities

us-gaap:CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths
slg:DividendType, us-gaap:StatementEquityComponents
us-gaap:CommonStockDividendsPerShareCashPaid
slg:RealEstateByLocation, us-gaap:ConcentrationRiskByBenchmark, us-gaap:ConcentrationRiskByType
us-gaap:ConcentrationRiskPercentage1
us-gaap:MajorCustomers, us-gaap:ConcentrationRiskByBenchmark, us-gaap:ConcentrationRiskByType

us-gaap:DepreciationAndAmortization
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:DilutiveSecuritiesEffectOnBasicEarningsPerShareOther
us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
us-gaap:DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax

us-gaap:DistributedEarnings
us-gaap:ConsolidatedEntities

us-gaap:DividendsCommonStock
us-gaap:StatementEquityComponents

us-gaap:DividendsPreferredStock
us-gaap:StatementEquityComponents

us-gaap:EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount

us-gaap:EquityMethodInvestmentDividendsOrDistributions
us-gaap:ConsolidatedEntities

us-gaap:EquityMethodInvestmentRealizedGainLossOnDisposal
us-gaap:ConsolidatedEntities
us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:EquityMethodInvestmentSummarizedFinancialInformationNetIncomeLoss
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:EquityMethodInvestmentSummarizedFinancialInformationRevenue

us-gaap:FinanceLeaseInterestExpense

us-gaap:FinanceLeasePrincipalPayments
us-gaap:ConsolidatedEntities

us-gaap:FinanceLeaseRightOfUseAssetAmortization
us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
us-gaap:FinancingReceivableAllowanceForCreditLossesWriteOffs

us-gaap:GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes
us-gaap:ConsolidatedEntities
us-gaap:StatementGeographical

us-gaap:GainsLossesOnSalesOfInvestmentRealEstate
us-gaap:ConsolidatedEntities
us-gaap:StatementGeographical
us-gaap:StatementGeographical, us-gaap:StatementScenario, us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:IncomeLossFromEquityMethodInvestments
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:IncreaseDecreaseInDeferredLeasingFees
us-gaap:ConsolidatedEntities

us-gaap:IncreaseDecreaseInDeferredLiabilities
us-gaap:ConsolidatedEntities

us-gaap:IncreaseDecreaseInDueFromRelatedPartiesCurrent
us-gaap:ConsolidatedEntities

us-gaap:IncreaseDecreaseInOtherOperatingAssets
us-gaap:ConsolidatedEntities

us-gaap:IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

us-gaap:InterestCostsIncurredCapitalized

us-gaap:InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet
us-gaap:DerivativeInstrumentRisk
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:InvestmentIncomeInterestAndDividend
us-gaap:ConsolidatedEntities

us-gaap:MarketableSecuritiesUnrealizedGainLoss
us-gaap:ConsolidatedEntities
us-gaap:MinorityInterestDecreaseFromRedemptions
us-gaap:ConsolidatedEntities, us-gaap:StatementClassOfStock

us-gaap:MortgageLoansOnRealEstateAmortizationOfPremium
us-gaap:InvestmentType
us-gaap:MortgageLoansOnRealEstateNewMortgageLoans
us-gaap:ConsolidatedEntities
us-gaap:NetIncomeLossNetOfTaxPerOutstandingLimitedPartnershipUnitDiluted
us-gaap:ConsolidatedEntities
us-gaap:NetIncomeLossPerOutstandingLimitedPartnershipUnitBasicNetOfTax

us-gaap:NoncontrollingInterestInNetIncomeLossOperatingPartnershipsRedeemable
us-gaap:ConsolidatedEntities

us-gaap:NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable
us-gaap:ConsolidatedEntities

us-gaap:NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities
us-gaap:NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance

us-gaap:OperatingLeaseCost
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:OperatingLeaseExpense

us-gaap:OperatingLeaseLeaseIncome
us-gaap:ConsolidatedEntities

us-gaap:OperatingLeaseLeaseIncomeLeasePayments

us-gaap:OperatingLeaseVariableLeaseIncome

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax
us-gaap:RelatedPartyTransactionsByRelatedParty, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax
us-gaap:DerivativeInstrumentRisk
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest
us-gaap:ConsolidatedEntities

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax
us-gaap:ConsolidatedEntities

us-gaap:OtherNoncashIncomeExpense
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities
us-gaap:PartnersCapitalAccountDistributions
us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents

us-gaap:PartnersCapitalAccountRedemptions
us-gaap:ConsolidatedEntities

us-gaap:PaymentsForRepurchaseOfRedeemablePreferredStock
us-gaap:ConsolidatedEntities

us-gaap:PaymentsRelatedToTaxWithholdingForShareBasedCompensation
us-gaap:ConsolidatedEntities

us-gaap:PaymentsToAcquireCommercialRealEstate
us-gaap:ConsolidatedEntities

us-gaap:PaymentsToAcquireEquityMethodInvestments
us-gaap:ConsolidatedEntities

us-gaap:PaymentsToMinorityShareholders
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities
us-gaap:PreferredStockDividendsAndOtherAdjustments
us-gaap:ConsolidatedEntities, us-gaap:StatementClassOfStock
us-gaap:PreferredStockDividendsPerShareCashPaid
us-gaap:StatementClassOfStock
us-gaap:ProceedsFromIssuanceOfCommonStock

us-gaap:ProceedsFromIssuanceOfSecuredDebt
us-gaap:ConsolidatedEntities

us-gaap:ProceedsFromOtherDebt
us-gaap:ConsolidatedEntities

us-gaap:ProceedsFromRealEstateAndRealEstateJointVentures
us-gaap:ConsolidatedEntities

us-gaap:ProceedsFromSaleAndMaturityOfMarketableSecurities
us-gaap:ConsolidatedEntities

us-gaap:ProceedsFromSaleOfAvailableForSaleSecuritiesDebt

us-gaap:ProceedsFromStockOptionsExercised
us-gaap:ConsolidatedEntities

us-gaap:ProvisionForLoanAndLeaseLosses
us-gaap:ConsolidatedEntities

us-gaap:ProvisionForLoanLeaseAndOtherLosses
us-gaap:ConsolidatedEntities

us-gaap:ProvisionForLoanLossesExpensed
us-gaap:CumulativeEffectPeriodOfAdoption

us-gaap:RealEstateTaxExpense
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax
us-gaap:RelatedPartyTransactionsByRelatedParty, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RelatedPartyTransactionOtherRevenuesFromTransactionsWithRelatedParty

us-gaap:RepaymentsOfOtherDebt
us-gaap:ConsolidatedEntities

us-gaap:RepaymentsOfSecuredDebt
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RevenueFromRelatedParties

us-gaap:RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability
us-gaap:ConsolidatedEntities

us-gaap:SalesTypeLeaseInterestIncome

us-gaap:SalesTypeLeaseLeaseIncome

us-gaap:SalesTypeLeaseSellingProfitLoss
us-gaap:PlanName
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardDiscountFromMarketPriceOfferingDate
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice
us-gaap:StatementEquityComponents
us-gaap:StockDividendsShares
us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents
us-gaap:StockIssuedDuringPeriodSharesDividendReinvestmentPlan
us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodValueDividendReinvestmentPlan
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodValueStockDividend
us-gaap:StatementEquityComponents

us-gaap:StraightLineRent
us-gaap:ConsolidatedEntities

us-gaap:SubleaseIncome
us-gaap:Ownership
us-gaap:SubsidiaryOfLimitedLiabilityCompanyOrLimitedPartnershipOwnershipInterest

us-gaap:TransferOfInvestments
us-gaap:ConsolidatedEntities

us-gaap:TreasuryStockAcquiredAverageCostPerShare
us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents
us-gaap:TreasuryStockSharesAcquired
us-gaap:StatementEquityComponents

us-gaap:TreasuryStockValueAcquiredCostMethod
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

us-gaap:UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic
us-gaap:ConsolidatedEntities

us-gaap:UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities
us-gaap:WeightedAverageLimitedPartnershipUnitsOutstanding
us-gaap:ConsolidatedEntities
us-gaap:WeightedAverageLimitedPartnershipUnitsOutstandingDiluted

dei:EntityCommonStockSharesOutstanding
us-gaap:ConsolidatedEntities

slg:AccruedInterestPayableAndOther
slg:InvestmentsByConsolidatedAndNonconsolidatedEntities
slg:InvestmentsByConsolidatedAndNonconsolidatedEntities, us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities

slg:AccumulatedAmortizationOfDeferredCosts

slg:BuildingLeaseholdImprovementsGross
us-gaap:ConsolidatedEntities

slg:DebtAndEquitySecuritiesWeightedAverageRiskRating
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty
slg:DebtInvestmentsOther

slg:DiscountOfStructuredFinanceInvestments
us-gaap:ConsolidatedEntities

slg:EmploymentAgreementsMinimumCashBasedCompensationInNextFiscalYear
us-gaap:RelatedPartyTransactionsByRelatedParty
slg:EquityMethodInvestmentsWithNegativeBookValue

slg:FinanceLeaseLiabilityPaymentsDueAfterYearSix

slg:FinanceLeaseLiabilityPaymentsDueYearSix

slg:FinancingReceivableRecordedInOtherAssets

slg:FiniteLivedIntangibleLiabilitiesAccumulatedAmortization

slg:FiniteLivedIntangibleLiabilitiesGross

slg:FiniteLivedIntangibleLiabilitiesNet
us-gaap:DebtInstrument, us-gaap:RelatedPartyTransactionsByRelatedParty
slg:FutureAmortizationOfDebt
us-gaap:DebtInstrument, us-gaap:RelatedPartyTransactionsByRelatedParty
slg:FutureAmortizationOfDebtAfterFifthFullFiscalYear
us-gaap:DebtInstrument, us-gaap:RelatedPartyTransactionsByRelatedParty
slg:FutureAmortizationOfDebtFifthFullFiscalYear
us-gaap:DebtInstrument, us-gaap:RelatedPartyTransactionsByRelatedParty
slg:FutureAmortizationOfDebtFirstFullFiscalYear
us-gaap:DebtInstrument, us-gaap:RelatedPartyTransactionsByRelatedParty
slg:FutureAmortizationOfDebtFourthFullFiscalYear
us-gaap:DebtInstrument, us-gaap:RelatedPartyTransactionsByRelatedParty
slg:FutureAmortizationOfDebtSecondFullFiscalYear
us-gaap:DebtInstrument, us-gaap:RelatedPartyTransactionsByRelatedParty
slg:FutureAmortizationOfDebtThirdFullFiscalYear
us-gaap:DebtInstrument, us-gaap:RelatedPartyTransactionsByRelatedParty
slg:FutureAmortizationofDebtRemainderOfFiscalYear
us-gaap:ConsolidatedEntities
slg:GeneralAndLimitedPartnersCapitalAccount
slg:LeasePaymentPeriod, us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:SubsequentEventType
slg:GrossTenantBillingsCollectedPercent
slg:LeasePaymentPeriod, us-gaap:SubsequentEventType
us-gaap:StatementGeographical
slg:InvestmentInJointVentureAggregateEquityCommittedByPartner
us-gaap:StatementGeographical
slg:InvestmentInJointVentureAggregateMaximumOwnershipPercentage
us-gaap:StatementGeographical
slg:InvestmentinJointVenturePartnersOwnershipPercentage

slg:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearSix

slg:LesseeOperatingLeaseLiabilityPaymentsDueYearSix
us-gaap:ConsolidatedEntities
slg:LimitedPartnershipUnitsHeldByGeneralPartner
us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
slg:LineOfCreditFacilityOptionalExpansionMaximumBorrowingCapacity

slg:LongTermDebtMaturitiesRepaymentsOfPrincipal
us-gaap:DebtInstrument, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RelatedPartyTransactionsByRelatedParty

slg:LongTermDebtMaturityAfterYearFour
us-gaap:DebtInstrument, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:FairValueByMeasurementBasis
slg:MortgageLoansOnRealEstateFairValueHighEndOfRange
us-gaap:FairValueByMeasurementBasis
slg:MortgageLoansOnRealEstateFairValueLowEndOfRange
us-gaap:MortgageLoansOnRealEstateLoanType
slg:MortgageLoansOnRealEstateLoanValue

slg:MortgageLoansonRealEstateCommercialandConsumerNetIncludingDebtInvestmentsOther

slg:MortgageLoansonRealEstateSeniorFinancing
us-gaap:MortgageLoansOnRealEstateLoanType

slg:OtherComprehensiveIncomeLossDeferredNetLossfromTerminatedHedges
us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations, us-gaap:SubsequentEventType
slg:OwnershipPercentageRetainedByInvestee

slg:RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionOfBuildingAndImprovements

slg:RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionOfLand

slg:RealEstateWeightedAverageOccupancy
slg:RealEstateByLocation
slg:RealEstateByLocation, us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:StatementGeographical
us-gaap:StatementGeographical
us-gaap:RelatedPartyTransactionsByRelatedParty
slg:SecuredDebtAndOtherLoansPayable

slg:SecuredDebtBearingFixedInterestAmount

slg:SecuredDebtBearingVariableInterestAmount

slg:SecuredDebtDeferredFinanceCostsNet

slg:SecuredDebtGross
us-gaap:RelatedPartyTransactionsByRelatedParty
slg:SecuredDebtandOtherLoansPayableNet
us-gaap:LongtermDebtType
slg:SeniorNotesNetofDeferredFinanceCosts
us-gaap:PlanName
slg:ShareBasedCompensationArrangementbyShareBasedPaymentAwardFungibleUnitsPerShare
us-gaap:PlanName
slg:SharebasedCompensationArrangementBySharebasedPaymentAwardNumberOfFungibleUnitsAvailableForGrant

slg:VariableInterestEntityNotPrimaryBeneficiaryInvestment

srt:RealEstateAndAccumulatedDepreciationAmountOfEncumbrances
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty

srt:RealEstateFederalIncomeTaxBasis

us-gaap:AccountsAndNotesReceivableNet
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent
us-gaap:ConsolidatedEntities

us-gaap:AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables

us-gaap:AllowanceForLoanAndLeaseLossesRealEstate
us-gaap:ConsolidatedEntities

us-gaap:AreaOfRealEstateProperty

us-gaap:AssetsNeededForImmediateSettlementAggregateFairValue
us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations, us-gaap:SubsequentEventType
us-gaap:AssetsOfDisposalGroupIncludingDiscontinuedOperation
us-gaap:FinancialInstrument
us-gaap:AvailableForSaleDebtSecuritiesAmortizedCostBasis

us-gaap:AvailableForSaleSecuritiesDebtSecurities
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FinancialInstrument
us-gaap:FairValueByMeasurementBasis
us-gaap:FinancialInstrument

us-gaap:BelowMarketLeaseAccumulatedAmortization
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:BelowMarketLeaseAmortizationIncomeNextTwelveMonths
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:BelowMarketLeaseAmortizationIncomeYearFive
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:BelowMarketLeaseAmortizationIncomeYearFour
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:BelowMarketLeaseAmortizationIncomeYearThree
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:BelowMarketLeaseAmortizationIncomeYearTwo

us-gaap:BelowMarketLeaseGross

us-gaap:BelowMarketLeaseNet
us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets

us-gaap:CollateralAlreadyPostedAggregateFairValue

us-gaap:ContractWithCustomerLiability
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentCarryingAmount
us-gaap:LongtermDebtType
us-gaap:FinancialInstrument
us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months
us-gaap:MortgageLoansOnRealEstateLoanType
us-gaap:DebtWeightedAverageInterestRate

us-gaap:DeferredCostsCurrentAndNoncurrent
us-gaap:ConsolidatedEntities

us-gaap:DeferredCostsLeasingAccumulatedAmortization

us-gaap:DeferredCostsLeasingGross

us-gaap:DeferredCostsLeasingNet
us-gaap:ConsolidatedEntities

us-gaap:DeferredFinanceCostsNet
us-gaap:LongtermDebtType
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:DeferredRentReceivablesNet
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:DeferredRevenue
us-gaap:DerivativeInstrumentRisk, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:DerivativeAssetNotionalAmount

us-gaap:DerivativeFairValueOfDerivativeAsset
us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeInstrumentRisk, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:BalanceSheetLocation
us-gaap:DerivativeFairValueOfDerivativeLiability
us-gaap:BalanceSheetLocation, us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:DerivativeNetLiabilityPositionAggregateFairValue
us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
us-gaap:DisposalGroupIncludingDiscontinuedOperationConsideration
us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations, us-gaap:SubsequentEventType

us-gaap:DividendsPayableCurrentAndNoncurrent
us-gaap:ConsolidatedEntities

us-gaap:DueFromJointVentures

us-gaap:DueFromOtherRelatedParties

us-gaap:DueFromRelatedParties
us-gaap:ConsolidatedEntities

us-gaap:EmployeeRelatedLiabilitiesCurrentAndNoncurrent
us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:AwardType
us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized

us-gaap:EquityMethodInvestmentDifferenceBetweenCarryingAmountAndUnderlyingEquity
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:EquityMethodInvestmentSummarizedFinancialInformationAssets
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:EquityMethodInvestmentSummarizedFinancialInformationEquity
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:EquityMethodInvestmentSummarizedFinancialInformationLiabilitiesAndEquity

us-gaap:EquityMethodInvestments
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:ConsolidatedEntities, us-gaap:FederalHomeLoanBankAdvancesOption
us-gaap:FederalHomeLoanBankAdvancesBranchOfFHLBBankAmountOfAdvancesByBranch

us-gaap:FinanceLeaseLiability
slg:InvestmentsByConsolidatedAndNonconsolidatedEntities
slg:InvestmentsByConsolidatedAndNonconsolidatedEntities, us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities

us-gaap:FinanceLeaseLiabilityPaymentsDue

us-gaap:FinanceLeaseLiabilityPaymentsDueAfterYearFive

us-gaap:FinanceLeaseLiabilityPaymentsDueNextTwelveMonths

us-gaap:FinanceLeaseLiabilityPaymentsDueYearFive

us-gaap:FinanceLeaseLiabilityPaymentsDueYearFour

us-gaap:FinanceLeaseLiabilityPaymentsDueYearThree

us-gaap:FinanceLeaseLiabilityPaymentsDueYearTwo

us-gaap:FinanceLeaseLiabilityPaymentsRemainderOfFiscalYear

us-gaap:FinanceLeaseLiabilityUndiscountedExcessAmount

us-gaap:FinanceLeaseRightOfUseAsset
us-gaap:ConsolidatedEntities
us-gaap:MortgageLoansOnRealEstateLoanType
us-gaap:FinancingReceivableAllowanceForCreditLosses

us-gaap:FinancingReceivableNonaccrualNoAllowance

us-gaap:FinancingReceivableOriginatedInCurrentFiscalYear
us-gaap:InternalCreditAssessment

us-gaap:FinancingReceivableOriginatedInFiscalYearBeforeLatestFiscalYear
us-gaap:InternalCreditAssessment

us-gaap:FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear
us-gaap:InternalCreditAssessment

us-gaap:FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear
us-gaap:InternalCreditAssessment

us-gaap:FinancingReceivableRecordedInvestmentNonaccrualStatus

us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFive
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFour
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearThree
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo

us-gaap:FiniteLivedIntangibleAssetsGross
us-gaap:ConsolidatedEntities
us-gaap:GeneralPartnersCapitalAccountUnitsOutstanding

us-gaap:InterestPayableCurrentAndNoncurrent
us-gaap:ConsolidatedEntities

us-gaap:InvestmentBuildingAndBuildingImprovements
slg:InvestmentsByConsolidatedAndNonconsolidatedEntities
slg:InvestmentsByConsolidatedAndNonconsolidatedEntities, us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities
us-gaap:InvestmentType
us-gaap:InvestmentOwnedUnderlyingFaceAmountAtMarketValue
us-gaap:MortgageLoansOnRealEstateLoanType, us-gaap:InvestmentType

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths

us-gaap:LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear

us-gaap:LessorOperatingLeasePaymentsToBeReceived
us-gaap:AccountsNotesLoansAndFinancingReceivableByReceivableType

us-gaap:LessorOperatingLeasePaymentsToBeReceivedFiveYears

us-gaap:LessorOperatingLeasePaymentsToBeReceivedFourYears

us-gaap:LessorOperatingLeasePaymentsToBeReceivedNextTwelveMonths

us-gaap:LessorOperatingLeasePaymentsToBeReceivedThereafter

us-gaap:LessorOperatingLeasePaymentsToBeReceivedThreeYears

us-gaap:LessorOperatingLeasePaymentsToBeReceivedTwoYears
us-gaap:DebtInstrument
us-gaap:LettersOfCreditOutstandingAmount
dei:LegalEntity
us-gaap:LiabilityForClaimsAndClaimsAdjustmentExpense
us-gaap:ConsolidatedEntities
us-gaap:LimitedPartnersCapitalAccount
us-gaap:ConsolidatedEntities
us-gaap:LimitedPartnersCapitalAccountUnitsOutstanding

us-gaap:LineOfCredit
us-gaap:ConsolidatedEntities
us-gaap:DebtInstrument
us-gaap:DebtInstrument
us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity
us-gaap:FairValueByMeasurementBasis
us-gaap:LongTermDebtFairValue

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive
us-gaap:DebtInstrument, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths
us-gaap:DebtInstrument, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive
us-gaap:DebtInstrument, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour
us-gaap:DebtInstrument, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree
us-gaap:DebtInstrument, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo
us-gaap:DebtInstrument, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear
us-gaap:DebtInstrument, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:LongtermDebtPercentageBearingFixedInterestAmount
us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:LongtermDebtPercentageBearingVariableInterestAmount
us-gaap:FairValueByMeasurementBasis

us-gaap:MarketableSecurities
us-gaap:ConsolidatedEntities
us-gaap:FairValueByMeasurementBasis
us-gaap:FinancialInstrument
us-gaap:ConsolidatedEntities
us-gaap:MinorityInterestInOperatingPartnerships
us-gaap:ConsolidatedEntities, us-gaap:StatementClassOfStock
us-gaap:MinorityInterestInPreferredUnitHolders
us-gaap:ConsolidatedEntities, us-gaap:Ownership
us-gaap:MinorityInterestOwnershipPercentageByNoncontrollingOwners
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:Ownership
us-gaap:MinorityInterestOwnershipPercentageByParent

us-gaap:MortgageLoansOnRealEstate
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty

us-gaap:MortgageLoansOnRealEstateCommercialAndConsumerNet

us-gaap:NonredeemableNoncontrollingInterest

us-gaap:NotesReceivableGross
us-gaap:InternalCreditAssessment
us-gaap:LongtermDebtType
us-gaap:MortgageLoansOnRealEstateLoanType, us-gaap:LongtermDebtType
us-gaap:MortgageLoansOnRealEstateLoanType
us-gaap:NotesReceivableNet

us-gaap:OperatingLeaseWeightedAverageDiscountRatePercent

us-gaap:OtherLiabilities
slg:InvestmentsByConsolidatedAndNonconsolidatedEntities
slg:InvestmentsByConsolidatedAndNonconsolidatedEntities, us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:OtherMinorityInterests
us-gaap:ConsolidatedEntities
us-gaap:PartnersCapital
us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents
us-gaap:PartnersCapitalAccountUnits
us-gaap:ConsolidatedEntities
us-gaap:PartnersCapitalAttributableToNoncontrollingInterest
us-gaap:ConsolidatedEntities
us-gaap:PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents
us-gaap:ConsolidatedEntities, us-gaap:StatementEquityComponents

us-gaap:RealEstateAccumulatedDepreciation

us-gaap:RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements

us-gaap:RealEstateAndAccumulatedDepreciationCarryingAmountOfLand

us-gaap:RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements

us-gaap:RealEstateAndAccumulatedDepreciationInitialCostOfLand

us-gaap:RealEstateGrossAtCarryingValue

us-gaap:RealEstateInvestmentPropertyAccumulatedDepreciation
slg:InvestmentsByConsolidatedAndNonconsolidatedEntities
slg:InvestmentsByConsolidatedAndNonconsolidatedEntities, us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities

us-gaap:RealEstateInvestmentPropertyAtCost
us-gaap:ConsolidatedEntities

us-gaap:RealEstateInvestmentPropertyNet
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:RedeemableNoncontrollingInterestEquityCommonCarryingAmount

us-gaap:RedeemableNoncontrollingInterestEquityPreferredCarryingAmount
us-gaap:ConsolidatedEntities

us-gaap:RestrictedCashAndCashEquivalents
us-gaap:ConsolidatedEntities

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceived

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedFiveYears

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedFourYears

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedNextTwelveMonths

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedThereafter

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedThreeYears

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedTwoYears

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivableUndiscountedExcessAmount

us-gaap:SalesTypeLeaseNetInvestmentInLease

us-gaap:SecuredDebt
slg:InvestmentsByConsolidatedAndNonconsolidatedEntities
slg:InvestmentsByConsolidatedAndNonconsolidatedEntities, us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:SecurityDepositLiability
us-gaap:ConsolidatedEntities

us-gaap:SeniorNotes
us-gaap:ConsolidatedEntities
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:LongtermDebtType
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice
us-gaap:StatementEquityComponents
us-gaap:SharePrice
us-gaap:ShareRepurchaseProgram
us-gaap:StockRepurchaseProgramAuthorizedAmount1

us-gaap:TreasuryStockShares

us-gaap:UnamortizedLoanCommitmentAndOriginationFeesAndUnamortizedDiscountsOrPremiums
us-gaap:ConsolidatedEntities

us-gaap:UnsecuredDebt
us-gaap:ConsolidatedEntities

Plots across concepts


IncomeStatement
Other Comprehensive Income Loss Net Of Tax
Expenses
Income Tax Expense Benefit
Balance Sheet
Finite Lived Intangible Assets Net
Assets
Cash And Cash Equivalents At Carrying Value
Current Assets
Cash And Cash Equivalents At Carrying Value
NonCurrent Assets
Finite Lived Intangible Assets Net
Liabilities
Dividends Payable Current And Noncurrent
Noncurrent Liabilities
Long Term Debt
Stockholders Equity
Accumulated Other Comprehensive Income Loss Net Of Tax
CashFlow
Net Cash Provided By Used In Financing Activities
NetCashProvidedByUsedInOperatingActivities
Increase Decrease In Accounts Receivable
NetCashProvidedByUsedInInvestingActivities
Payments To Acquire Investments
NetCashProvidedByUsedInFinancingActivities
Net Cash Provided By Used In Financing Activities
Shares
Treasury Stock Shares
DividendsAndRepurchase
Dividends Payable Current And Noncurrent
LesseeOperatingLeaseLiabilityPaymentsDue
Lessee Operating Lease Liability Payments Remainder Of Fiscal Year
FiniteLivedIntangibleAssets
Finite Lived Intangible Assets Net

Tables

  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
us-gaap:CommonStockValue ▁▁▂▂▂▃▃▄▄▄▄▅▅▅▆▇▇███▇▇▇████▇▇▇▇▆▆▆▆▆▆▆▅▅▅▄▄0.690.7050.7160.7410.7480.7760.8030.8260.8350.8430.8470.8670.8680.9020.9390.9850.9951.0191.0171.0131.0031.0021.0011.0341.0331.0321.010.9960.9930.990.9860.9590.9550.9530.950.940.9360.9250.8920.8920.8780.8440.817NANA
 us-gaap:SharesOutstanding us-gaap:StatementEquityComponents us-gaap:CommonStock▁▁▁▂▂▃▃▄▄▄▄▅▅▆▆▇▇█████████▇▇▇▇▇▆▆▆▆▆▆▅▅▅67.8869.35468.50873.0473.67576.53579.20281.51582.4183.27283.68485.59485.72589.13592.80397.44698.367100.776100.562100.264100.164100.08199.97699.65999.5999.53397.32595.94595.58795.31994.99392.21491.81277191.55591.2590.36389.93888.85585.78385.706NANA78.307NANA
us-gaap:CommonStockSharesIssued ▁▁▁▂▂▃▃▄▄▄▄▅▅▅▆▇▇██▇▇▇▇████▇▇▇▇▆▆▆▆▆▆▆▅▅▅▄▄68.90670.3869.53474.09574.7377.59180.25882.5783.46584.32884.73986.64986.7890.1993.85898.50199.422101.831101.617100.319100.164100.168100.063103.383103.233103.176100.92899.54799.18898.91998.56395.7895.37695.20194.89693.9793.54392.4689.2189.13387.72384.33681.675NANA
us-gaap:CommonStockSharesOutstanding ▁▁▁▂▂▃▃▄▄▄▄▅▅▅▆▇▇██▇▇▇▇████▇▇▇▇▆▆▆▆▆▆▆▅68.90670.3869.53474.09574.7377.59180.25882.5783.46584.32884.73986.64986.7890.1993.85898.50199.422101.831101.617100.319100.164100.168100.063103.383103.233103.176100.92899.54799.18898.91998.56395.7895.37695.20194.89693.9793.54392.4689.21NA87.72384.33681.675NANA
us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding ▁█73.72774.07NA77.49180.21982.567NA86.71487.39887.81NA90.42892.08395.256NA102.57104.732105.554NA105.143104.792104.259NA103.92999.579103.019NA99.70699.48498.716NA95.01694.53694.302NA93.89193.35190.173NA88.08186.0181.643NA79.78179.791
us-gaap:WeightedAverageNumberOfSharesOutstandingBasic ▁█68.9869.01NA73.0275.6977.864NA82.29282.97183.313NA85.56687.17690.52NA97.78399.9100.643NA100.233100.134100.051NA99.62199.57998.402NA95.73495.45595.117NA91.98891.6691.399NA90.24189.78986.744NA85.69683.57879.401NA78.22778.046
us-gaap:EarningsPerShareBasic ▃▂▄▂▂▃▂▂▄▂▁▃▃▃▂▂▂▂▂▂▃▂▃▃▁▂▂▂▄▃▂▂▂▂▂▂▃▂▂▂█▃▂▃▃1.52-0.112.440.190.741.470.210.41.940.52-0.731.031.191.120.290.40.080.110.440.341.330.231.021.64-0.390.440.590.682.471.540.390.40.090.210.230.091.150.290.030.086.31.020.091.431.76
us-gaap:EarningsPerShareDiluted ▃▂▄▂▂▃▂▂▄▂▁▃▃▃▂▂▂▂▂▂▃▂▃▃▁▂▂▂▄▃▂▂▂▂▂▂▃▂▂▂█▃▂▃▃1.51-0.112.430.190.741.470.210.41.940.52-0.731.031.191.120.290.40.080.110.440.341.330.231.02000000000000021.64-0.390.440.590.682.461.530.390.40.090.210.230.091.140.290.030.086.261.010.091.421.75
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
 Cost Ratio us-gaap:ConsolidatedEntities srt:Subsidiaries▁█218.107226.102NA249.844253.699314.303NA313.634313.024304.255NA307.545301.116301.695NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 Cost Ratio us-gaap:RelatedPartyTransactionsByRelatedParty us-gaap:CorporateJointVenture▁█289.188301.541NANA271.518282.52NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 Net profit Margin us-gaap:ConsolidatedEntities srt:Subsidiaries▁▂▂▃▄█▇██▇█▇▇▇218.107226.102234.898249.844253.699314.303308.082313.634313.024304.255317.036307.545301.116301.695NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 SG&A Ratio us-gaap:ConsolidatedEntities srt:Subsidiaries▁▂▂▃▄█▇██▇█▇▇▇218.107226.102234.898249.844253.699314.303308.082313.634313.024304.255317.036307.545301.116301.695NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
 us-gaap:AllocatedShareBasedCompensationExpense us-gaap:AwardType slg:RestrictedStockAwards▂▁▃▅▅▅█▇▅█2.1918062.0671252.3664682.8373052.7619052.9297813.4226273.1374542.9203273.411841NA3.1898083.1163753.134975NA2.4227042.4734242.3809261.8781671.9033651.355882.0165541.8775511.8511671.8751761.9368532.3900962.5896542.3376022.3406672.2916041.4502121.5071161.4642231.642012NANANANANANANANANANA
 us-gaap:AllocatedShareBasedCompensationExpense us-gaap:AwardType us-gaap:PerformanceShares▄▄9.19.1NA6.46.77.3NA3.03.08.0NA2.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:AllocatedShareBasedCompensationExpense us-gaap:AwardType,us-gaap:PlanName us-gaap:EmployeeStockOption,slg:ThirdAmendmentandRestated2005StockOptionandIncentivePlanNANA-0.030.00.010.020.70.60.60.61.11.11.61.61.92.01.90.02.52.51.92.02.21.91.92.02.12.02.02.1NANANANANANANANANANANANANANANA
 us-gaap:AllocatedShareBasedCompensationExpense us-gaap:PlanName slg:DeferredStockCompensationPlanForDirectors▁▇▁▁▁▇▁▁▁▇▁▁▁█▁▁▁▇▁▁▁▆▁▁▂▅▁▁▁0.21.80.20.20.21.80.20.20.21.90.20.10.12.20.20.10.21.90.20.10.21.60.10.10.31.30.10.10.1NANANANANANANANANANANANANANANANA
us-gaap:ComprehensiveIncomeNetOfTax ▃▂▄▂▃▃▂▂▄▂▁▃▃▃▂▂▂▂▃▂▄▂▃▄▂▂▃▃▅▄▂▂▂▂▂▂▃▂▂▂█▃61.10344.624183.69123.76858.67866.15632.81625.158140.4528.417-78.67395.624111.343115.47336.13842.4389.8029.46383.96440.474137.85818.486112.113162.481-34.46442.18556.43971.726247.955150.16744.89540.13634.9329.78627.05714.779106.54737.2676.3711.751525.42798.08NANANA
us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest ▃▂▄▂▃▃▂▂▄▂▁▃▃▃▂▂▂▂▃▂▄▂▃▄▂▂▃▃▅▄▂▂▂▂▂▂▃▂▂▂█▃66.32747.15209.65827.16565.02971.84536.49528.378148.09332.653-80.652103.341120.194124.41142.96345.62213.758-4.90191.73745.945149.70623.708121.603171.647-28.23350.60661.06977.007259.284156.90948.52144.68439.19933.86627.15927.703114.26739.04213.45413.548540.416103.629NANANA
us-gaap:CostsAndExpenses █▁43.88342.284NA45.9140.89753.866NA59.84758.31757.698NA56.85256.23759.782NA75.92770.85274.50678.5979.42575.32479.5276.08578.64870.11476.77771.16572.11170.67573.48674.61377.27269.43273.63372.15483.9868.91973.26971.90269.09762.40660.361.70358.06852.748
us-gaap:IncomeTaxExpenseBenefit ▅▄▁▃▅▅▅▅▄▅▅▄▅▄▆▃█0.80.7-0.80.00.91.11.01.00.70.80.80.31.10.51.50.12.2NA0.90.90.31.20.61.11.10.31.21.62.12.9-1.62.12.31.6-0.20.00.10.0-0.2NANANA0.0NANA
us-gaap:InterestExpense ▂▂▂▂▃▄▄▄▄▄▁▄▄▄▂▅▅▅▅▆▇█▇▆▆▆▆▆▆▆▆▆▆▆▆▆▆▆▆▆▅▄▄▄▄38.50139.86841.58942.59544.93756.81361.68563.60760.74560.8128.11964.07861.55354.91839.77272.85971.99272.42271.62578.71595.568102.15588.97184.91776.47276.45981.61383.15879.16380.71283.37183.53683.74681.78982.69986.21482.72880.54776.89575.93969.52864.75161.27356.9257.445
us-gaap:InterestIncomeExpenseNet ▂▂▂▂▂▂▆▁▁▁▆▁▁▁█▁▃▃▃▃▃▃▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁█▁▁▁-18.96-23.388-25.579-23.536-30.07-37.494336.318-48.112-47.16-50.525365.364-55.168-53.611-47.916453.157-65.63464.85665.62264.87372.56589.08994.672-88.176-84.141-75.746-75.807-80.976-82.376-78.611-80.18-82.795-82.973-83.276-81.336-82.277-85.828-82.327-80.137492.959-74.603-68.173-64.266NANANA
us-gaap:InterestIncomeOperating ▂▂▂▃▃▂▃▃█▃▃▂▂▂▂▂▂▂▃▁▄▃▃▃▃▃▃▃▂▂▃▃▂▂▂▂▂▂▂▂▂▂▃▂▂0.3640.3890.4520.580.6480.4990.5610.6082.3740.580.8870.4060.3480.3160.3150.3560.3930.5210.820.0661.0460.8650.7950.7760.7260.6520.6370.7820.5520.5320.5760.5630.470.4530.4220.3860.4010.410.4690.5110.5380.4850.7960.4780.504
us-gaap:NetIncomeLoss ▃▂▄▂▂▃▂▂▄▂▁▃▃▃▂▂▂▂▂▂▃▂▃▄▁▂▂▂▅▃▂▂▂▂▂▂▃▂▂▂█▃▂▃▃109.069-3.726174.73817.59760.181118.53921.16936.895164.8447.53-57.48291.947107.293105.50431.71942.60711.95915.08947.75337.99137.19426.959105.041167.396-35.36847.01560.52568.426239.279149.82840.85740.76327.43526.31627.36325.657110.58433.19810.35114.624534.00388.43214.754119.045144.583
us-gaap:NetIncomeLossAttributableToNoncontrollingInterest ▅▃█▄▅▅▄▄▅▄▃▅▅▅▅▄▄▁▅▄▆▄▅▅▅▅▄▄▅▅▄▄▄▄▄▄▅▄▅▄8.065-0.12925.6023.086.4468.5753.0863.8278.9015.239-0.8387.5078.6068.3196.6163.1884.056-14.1656.2175.35311.9015.5449.2089.3576.1898.6214.8025.16811.0536.7843.5054.5733.8134.0210.0942.9737.8732.3567.2021.864NANANANANA
us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic ▃▂▄▂▂▃▂▂▄▂▁▃▃▃▂▂▂▂▂▂▃▂▃▄▁▂▂▂▅▃▂▂▂▂▂▂▃▂▂▂█▃▂▃▃105.332-7.464171.00113.85956.444114.80117.43233.157161.10343.792-61.21988.209103.556101.76627.98238.8698.22211.35144.01634.252133.45723.221101.303163.658-39.10643.27756.78764.688235.541146.0937.1237.0258.27618.90919.9567.732103.0425.2562.8087.079526.45880.8877.209111.5137.038
us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted ▃▂▄▂▂▃▂▂▄▂▁▃▃▃▂▂▂▂▂▂▃▂▃▄▁▂▂▃▅▄▂▂▂▂▂▂▃▂▂▂█▃▂▃▃111.614-7.94180.94414.66159.514121.00318.40734.876169.41346.07-64.65993.006109.142107.03829.2740.6818.64111.82745.98135.915139.04324.143105.234170.126-39.10645.0259.24267.324244.186150.81938.23438.1358.5219.46420.6778.299106.46126.1443.4927.248538.38382.7397.239113.286139.505
us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax ▁█▅▅▄▁▅▄▃▃▃▅-51.31351.2638.4846.099-3.59-50.73512.562-12.574-26.22-20.884-22.4313.919NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax us-gaap:ConsolidatedEntities srt:Subsidiaries▁█▅▅▄▁▅▄▃▃▃▅-51.31351.2638.4846.099-3.59-50.73512.562-12.574-26.22-20.884-22.4313.919NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherComprehensiveIncomeLossNetOfTax ▁█▅▅▅▁▅▄▃▃▃▅▅▅▅▅▄▄▇▅▅▄▅▄▅▄▄▅▅▅▅▅▅▅▅▅▄▅▄▄-50.80751.0059.3186.488-1.598-55.26912.24-12.344-25.648-20.116-22.3323.8874.29510.5884.628-0.173-2.257-5.82537.7672.6020.611-8.7957.354-5.1060.946-5.03-4.2563.4138.9520.2974.159-0.6527.9513.529-0.298-0.927-4.193.885-4.101-2.94NANANANANA
 us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:ConsolidatedEntities srt:Subsidiaries▁█▅▅▅▁▅▄▃▃▃▅▅▅-50.80751.0059.3186.488-1.598-55.26912.24-12.344-25.648-20.116-22.3323.8874.29510.588NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherIncome ▂▂▂▃▂▄▂▂▂▂▂▁▂▂▁▁▂▂▁▁█▁▂▂▂▁▁▂▂▂▁▁▁▁▁▁▁▁▂▁▁▁▁▁▁13.38918.7425.80831.34117.8753.13915.20714.08816.44714.10611.5657.70213.42214.6379.3427.26615.50111.5616.2116.673107.9759.48913.00716.01918.259.9327.22311.18622.7514.5823.6529.8775.7265.7749.8049.2726.28210.37712.2226.0779.9327.24911.0298.0658.877
us-gaap:ProfitLoss ▃▂▄▂▂▃▂▂▄▂▁▃▃▃▂▂▂▂▂▂▃▂▃▄▁▂▂▃▅▃▂▂▂▂▂▂▃▂▂▂█▃▂▃▃117.134-3.855200.3420.67766.627127.11424.25540.722173.74152.769-58.3299.454115.899113.82338.33545.79516.0150.92453.9743.343149.09532.503114.249176.753-29.17955.63665.32573.594250.332156.61244.36245.33631.24830.33727.45728.63118.45735.15717.55516.488549.18793.89417.959124.566150.499
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService,us-gaap:RelatedPartyTransactionsByRelatedParty us-gaap:ManagementServiceBase,us-gaap:CorporateJointVenture▃▂█▁▁▁▃▂▃▂▄▂▂▃4.22.49.72.21.72.24.22.43.92.54.92.43.03.8NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:Revenues ▁▁▁▂▂▃▃▃▃▃▃▃▂▂▄▄▄▄▄▄█▅▅▅▄▄▄▄▄▄▄▄▄▄▃▄▃▃▃▃▂▃▂▃▂218.107226.102234.898249.844253.699314.303308.082313.634313.024304.255317.036307.545301.116301.695361.342374.6398.15377.381374.242416.681617.614455.444425.39432.066409.074396.299386.627390.274387.227381.128374.699363.765365.145369.971350.733361.441349.005339.192328.877308.574300.655334.322262.785319.151251.572
us-gaap:SellingGeneralAndAdministrativeExpense ▄▄▆▅▅▂▆▅▆▆▆▃▄▅█▅▅▅▆▆▅▅▄▅▄▆▄▄▅▄▄▃▃▃▃▃▃▂▁▁▄▂▃▁▁22.06422.88525.14423.60223.5119.5725.57523.84125.4825.97926.0320.59422.47923.52828.13623.96324.25624.14325.825.524.524.03222.76123.47523.225.46422.7122.64923.87223.25722.74220.86921.51421.06721.37120.55120.72120.19618.72818.922.45420.02120.69518.47418.379
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
us-gaap:Assets ▁▂▁▂▃▃▂▃▃▃▂▃▃▃▃▄▄▅▅▅▆███▆▆▆▆▅▄▄▄▄▄▄▄▃▃▃▃▂▁▁11166.16412044.04511707.56712324.03913071.56413220.60712766.3213294.98413629.94113385.77412751.35813455.00413713.92813380.8713982.90415109.8715309.70715877.27115857.78715790.94217544.22319585.96819857.94119490.56917266.95817080.73217096.58717237.10916717.73615363.28914959.00114574.91914401.92514543.96514387.75414284.93914139.11313761.71313483.85213162.64512644.07811442.36611300.294NANA
us-gaap:Liabilities ▁▂▂▂▃▃▂▂▃▂▂▂▂▁▂▃▃▃▃▃▅███▅▅▅▆▅▄▃▃▃▃▃▃▃▂▂▂▂▁▁5798.7036535.7986211.3416634.3857281.6527251.7286555.9756843.5367062.3316843.8056115.2716418.8016683.8776065.8496629.7617153.0357172.5227380.2797330.9847275.5449008.19211179.0311431.90211112.8749186.4348927.569096.7329419.2679016.1347897.2977627.0997508.2297385.2367368.5627218.1947110.2716998.5466822.0036833.5136635.2926224.4155682.7875818.412NANA
us-gaap:LiabilitiesAndStockholdersEquity ▁▂▁▂▃▃▂▃▃▃▂▃▃▃▃▄▄▅▅▅▆███▆▆▆▆▅▄▄▄▄▄▄▄▃▃▃▃▂▁▁11166.16412044.04511707.56712324.03913071.56413220.60712766.3213294.98413629.94113385.77412751.35813455.00413713.92813380.8713982.90415109.8715309.70715877.27115857.78715790.94217544.22319585.96819857.94119490.56917266.95817080.73217096.58717237.10916717.73615363.28914959.00114574.91914401.92514543.96514387.75414284.93914139.11313761.71313483.85213162.64512644.07811442.36611300.294NANA
us-gaap:StockholdersEquity ▁▁▁▂▂▂▃▃▄▄▄▅▅▆▅▇▇███████▇█▇▇▆▆▆▅▅▅▆▅▅▅▄▄▄▂▁4789.1324911.0264909.7635056.1125119.9725263.4665441.3155692.1485809.9225797.7995901.5216214.6586190.8166487.7856225.0936817.8856935.7127263.2617324.4757293.5557318.297268.1687287.4657238.327115.5097148.9356937.3746844.6246780.1226625.6926525.4056281.0156234.7966417.2466419.8026371.9126321.8126162.355975.5476028.5445869.0955095.9634879.084NANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
us-gaap:CashAndCashEquivalentsAtCarryingValue ▂▂▂▂█▄▁▁▁▁▁▁▂▂▁▂▂▄▂▃▂▃▂▂▂▃▂▂▂▄▂▂▂▂▂▁▂▁▁▃▃▂▃▂▃218.337304.999266.059221.4041015.348554.195166.07121.751148.978144.323129.475160.248287.24288.808127.888241.489270.965468.035279.443405.896276.226316.205255.399244.36215.896330.77281.409253.52308.103447.162206.692209.098198.969220.104189.984162.363256.799133.665138.192394.505390.229234.009332.83270.803339.577
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents ▂▂▂▂█▄▁▁▁▂▁▁▂▂▁▂▂▄▂316.501401.607372.795304.4491101.283621.022241.43216.544241.147295.711279.113258.592379.98378.265250.026349.252380.924539.25369.967NANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:Land ▁▁▁▂▂▂▂▂▂▂▂▂▂▃▃▄▄▅▅▅▇▇██▆▆▆▆▅▅▄▄▄▄▄▄▄▄▄▄▃▂▂1403.3991445.1991315.8321639.1181625.4831662.841751.5441860.9221929.4961775.0061774.8991827.9991893.0472098.4062357.0512917.9932936.8793295.053309.713347.4824108.8214115.9824779.1594689.0313756.4883830.7873844.5183833.3053466.5873112.0133032.5262868.8332866.0482886.0992886.0992937.8662872.8222816.8312684.6262581.9572472.5841974.9941750.22NANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
us-gaap:FiniteLivedIntangibleAssetsNet ▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▂▂▄▄▃██▇▇▇▇▄▄▅▆▆▆▆▆▆▇▇▇▆▇▆30.04535.17625.1516.08619.09722.44426.97530.08135.51422.29425.521.73723.79441.24548.84276.44685.938232.142240.169227.409602.263615.297535.771546.664541.961559.879281.061303.22319.958414.967403.365406.936435.587445.994462.754492.63500.247507.294480.053512.539409.635NA624.563NANA
us-gaap:OperatingLeaseRightOfUseAsset ██▆▆▆▆▇▇▇▇▁502.316502.316367.209381.255381.255381.255396.795396.795396.795396.1480.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
us-gaap:LongTermDebt NANA1979.972NANANA2183.253NANANA1961.24NANANA2837.2826477.0616435.3886664.5456568.7126519.6758081.57410084.70810458.81810157.6998406.258122.3648468.9748775.5078399.6477240.2436967.4926869.925-6721.936-6678.073-6520.42-6388.277-6278.024-6081.046-6094.496-5886.441-5597.585NANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument slg:TermLoan▄▄1500.01500.0NA1500.01500.0NANANANANANANANANANA1183.01183.01183.01183.01183.0933.0933.0933.0933.0833.0833.0833.0NANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType slg:CreditFacility2017,us-gaap:LineOfCreditNANA105.3NANANA234.0NANANA492.2NANANA30.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType slg:TermLoan,us-gaap:LineOfCredit███████████████▄▄▄▄▄▁▁▁1500.01500.01500.01500.01500.01500.01500.01500.01500.01500.01500.01500.01500.01500.01500.01200.01200.01200.01200.01200.0930.0929.8929.5NANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo ██▁█29.50229.50226.22829.452NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree ██▁▄30.54530.54523.92127.148NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour ██▁▂30.77230.77223.93924.844NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive ██▁▂30.91130.91124.02624.863NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive ██▁631.532631.532504.36NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
us-gaap:StockholdersEquity ▁▁▁▂▂▂▃▃▄▄▄▅▅▆▅▇▇███████▇█▇▇▆▆▆▅▅▅▆▅▅▅▄▄▄▂▁4789.1324911.0264909.7635056.1125119.9725263.4665441.3155692.1485809.9225797.7995901.5216214.6586190.8166487.7856225.0936817.8856935.7127263.2617324.4757293.5557318.297268.1687287.4657238.327115.5097148.9356937.3746844.6246780.1226625.6926525.4056281.0156234.7966417.2466419.8026371.9126321.8126162.355975.5476028.5445869.0955095.9634879.084NANA
us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest ▁▁▁▂▂▂▃▃▄▃▄▄▄▅▅▇▇███████▇█▇▇▇▆▆▆▆▆▆▆▆▅▅▅▄▃▂4813.7574935.624935.7955134.0055205.7625343.9655517.1985763.35879.5015844.3235947.8556267.1756242.0566537.6296589.4547184.0527347.647703.6847750.9117722.6487747.1197695.0237719.3177671.7587524.3837543.3767459.2167363.4537272.2477117.5847016.8766769.0946723.2146905.6796907.1036860.0256811.3326652.3976453.3096412.6276261.2455615.8235397.544NANA
us-gaap:CommonStockValue ▁▁▂▂▂▃▃▄▄▄▄▅▅▅▆▇▇███▇▇▇████▇▇▇▇▆▆▆▆▆▆▆▅▅▅▄▄0.690.7050.7160.7410.7480.7760.8030.8260.8350.8430.8470.8670.8680.9020.9390.9850.9951.0191.0171.0131.0031.0021.0011.0341.0331.0321.010.9960.9930.990.9860.9590.9550.9530.950.940.9360.9250.8920.8920.8780.8440.817NANA
us-gaap:AdditionalPaidInCapital ▂▂▂▂▂▃▃▄▄▄▄▄▄▅▆▇▇███▇▇▇███▇▆▆▆▆▅▅▅▅▄▄▄▃▃▃▂▁3823.293913.2583862.9493998.5164021.8914146.3064286.3954407.6674451.2094492.5814508.6854602.654601.6084776.5944968.3385294.55391.0385651.0895624.5455596.0265466.5935451.7875439.7355593.6535570.7465572.415289.4795130.8585085.9655049.5075015.9044757.7784716.0124697.5284667.94589.4234557.6524469.7774236.9594225.9034105.4423836.4533660.842NANA
us-gaap:RetainedEarningsAccumulatedDeficit ▁▁▂▂▂▂▂▃▄▃▄▅▅▆▃▅▅▆▆▆▇▆▇█▇▇███▇▆▇▇▇▇▇▇▇▇█▇▃▃934.132918.0771015.4621035.1721081.8211099.3691084.7191225.9041288.391210.4971278.9981476.9591457.8351583.8331139.3291410.3321431.4421496.7591578.8931612.7071655.321620.6691643.5461772.8331657.9111690.5781752.4041813.9561797.581688.2111619.151636.5841631.2871665.4681701.0921728.151741.161665.5471704.5061763.4031721.441207.5041172.963NANA
us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax ▂▅▂▁▁▁▄▃▄▆▇███▇▇▇▇▇▅▅▅▅▅▅▅▅▆▅▅▅▅▅▄▄▄▄▄▄▄▅▅▅-66.863-18.897-67.247-76.2-82.371-80.868-28.485-40.132-28.395-4.00515.10836.29932.62228.57318.60414.18514.35416.51122.137-14.074-16.558-17.222-8.749-15.821-10.906-11.81-6.98-2.896-6.196-14.872-15.211-19.249-18.622-26.117-29.587-29.281-28.413-24.376-28.445-24.462-21.589-13.011-22.659NANA
 us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax us-gaap:ConsolidatedEntities srt:Subsidiaries▂▆▂▁▁▁▅▄▅▇█-66.863-18.897-67.247-76.2-82.371-80.868-28.485-40.132-28.395-4.00515.108NANANA18.604NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:TreasuryStockValue ▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▁▁▁███████████████▇▇▇▇▇124.049124.049124.049124.049124.049124.049124.049124.049124.049124.049124.049124.049124.049124.049124.049124.049124.049124.049124.049124.04910.010.010.0335.311325.207325.207320.471320.222320.152320.076317.356316.989316.768322.858322.858319.905319.866319.866308.708307.535307.419306.17303.222NANA
us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders ▁█0.0630.11NA12.530.1040.492NA0.2070.0630.208NA1.1390.4480.2767.35744.480.140.4694.3961.1571.9617.9054.9561.880.848112.11.2741.3932.7661.5862.8143.6573.2734.8796.3243.6234.8827.1170.1059.762131.5022.21NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
us-gaap:NetCashProvidedByUsedInOperatingActivities ▃▁▇▃▆▂▃▃▅▂▄▃▅▃▄▃▆▄▄▄█▄▆▃▅▃▄▃▆▃▃▃▄▃▃▂▅▂▃▂▃▃▂▃▃84.66218.602226.293103.638182.27942.02677.0481.518155.60262.313123.99271.333151.66694.546131.752102.899197.563116.159125.922135.414259.288114.09203.48589.54142.590.959113.175100.644188.41488.14875.74996.966110.963102.52587.78768.021141.10456.83175.16460.84897.03979.80967.009101.39585.972
us-gaap:NetCashProvidedByUsedInInvestingActivities ▆▄▆▄▆▄▅▅▄▄▅▅▄▅▅▅▄▅▄▅█▅▄▁▃▅▄▃▄▄▄▄▅▄▄▄▄▄▄▄▄▅▄▄▅621.3420.181681.407-28.796533.237-129.418355.394225.504-174.561-291.843181.43232.168-187.938456.00282.19162.732-293.57729.804-282.603278.4261787.89338.857-279.485-1728.493-488.23230.29728.428-507.222-246.24-71.801-385.97-195.943127.968-174.49-341.217-271.129-263.855-294.192-238.078-436.786-95.73230.999-156.175-71.909307.142
us-gaap:NetCashProvidedByUsedInFinancingActivities ▃▅▃▃▄▆▄▄▅▅▄▄▅▄▄▄▅▅▅▄▁▄▅█▅▄▅▆▅▅▅▅▄▅▅▅▅▅▅▆▅▅▅▅▄-791.108-9.971-839.354-871.676-235.255466.984-407.548-331.625-35.605246.128-284.901-424.88937.987-422.309-327.543-295.107-101.05642.62930.228-284.17-2087.157-392.14187.0391667.417230.856-271.895-113.714351.995-81.233224.123307.815109.106-260.066102.085281.051108.672245.885232.834-93.399380.214154.913-209.629151.193-98.26-221.191
 us-gaap:NetCashProvidedByUsedInFinancingActivities us-gaap:ConsolidatedEntities srt:Subsidiaries▁▆▁▁▄█▃▄▅▇▄▃▆▃-791.108-9.971-839.354-871.676-235.255466.984-407.548-331.625-35.605246.128-284.901-424.88937.987-422.309NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect ▅▆▆▁█▇▆▅▅▅▅▅▅▆▅▅▄▆-85.10628.81268.346-796.834480.261379.59224.886-24.603-54.56416.59820.521-121.3881.715128.239-99.226-31.672-158.326169.283NANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect us-gaap:ConsolidatedEntities srt:Subsidiaries▅▆▆▁█▇▆▅▅▅▅▅▅▆-85.10628.81268.346-796.834480.261379.59224.886-24.603-54.56416.59820.521-121.3881.715128.239NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
us-gaap:AmortizationOfFinancingCosts ▃▃▃▃▂▂▃▃▂▂▂▂▃▃▄▄▃▅▄▅▇██▇▆▇▇▇▅▄▃▄▄▄█▄▃▃▄▃▂▃▃▂▁3.3863.7743.4823.1512.6612.53.0873.1122.7122.7422.6952.633.5463.5374.2974.0083.4324.7614.3844.8157.4337.9327.6217.165.9526.6156.646.6795.53.8683.6614.3314.244.4637.8244.4933.5533.584.632.9922.693.8063.482.5811.571
us-gaap:DepreciationDepletionAndAmortization ▁▁▁▂▂▁▁▁▁▁▁▁▁▁▂▂▃▂▂▂█▄▂▃▄▂▂▂▂▂▂▂▂▂▂▂▂▂▂▁▁▁▁▁▁60.64766.7760.41495.66798.60270.77967.17773.57672.17371.08574.15373.37771.4672.92588.70195.736136.48698.895108.41117.48432.475187.24114.421153.345205.517114.955104.124101.848100.34993.6892.76691.80587.88285.146101.58987.92281.36580.66379.75376.20372.85863.49750.48960.13955.373
us-gaap:IncreaseDecreaseInAccountsReceivable ▃▄▁▂▅█▃▄▃▄▃▃▃▄▄▄▄▃▃▄▄▃▃▄▅▃▃▅▄▂▄▄▄▃▄▄▄▄▄▄▄▃▃▄▃-1.6454.138-25.995-14.25612.36544.96-2.5966.455-3.654.759-3.782-3.583-1.451.8473.3993.765-0.175-1.272-2.0662.1063.009-7.829-2.0931.67213.922-7.096-9.31413.2266.009-11.8994.5527.9142.513-7.4092.4983.4945.02-0.0141.592.2891.866-1.025-3.6237.245-3.48
 us-gaap:IncreaseDecreaseInAccountsReceivable us-gaap:ConsolidatedEntities srt:Subsidiaries▃▄▁▂▅█▃▄▃▄▃▃▃▄-1.6454.138-25.995-14.25612.36544.96-2.5966.455-3.654.759-3.782-3.583-1.451.847NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:NetCashProvidedByUsedInOperatingActivities ▃▁▇▃▆▂▃▃▅▂▄▃▅▃▄▃▆▄▄▄█▄▆▃▅▃▄▃▆▃▃▃▄▃▃▂▅▂▃▂▃▃▂▃▃84.66218.602226.293103.638182.27942.02677.0481.518155.60262.313123.99271.333151.66694.546131.752102.899197.563116.159125.922135.414259.288114.09203.48589.54142.590.959113.175100.644188.41488.14875.74996.966110.963102.52587.78768.021141.10456.83175.16460.84897.03979.80967.009101.39585.972
us-gaap:NetIncomeLoss ▃▂▄▂▂▃▂▂▄▂▁▃▃▃▂▂▂▂▂▂▃▂▃▄▁▂▂▂▅▃▂▂▂▂▂▂▃▂▂▂█▃▂▃▃109.069-3.726174.73817.59760.181118.53921.16936.895164.8447.53-57.48291.947107.293105.50431.71942.60711.95915.08947.75337.99137.19426.959105.041167.396-35.36847.01560.52568.426239.279149.82840.85740.76327.43526.31627.36325.657110.58433.19810.35114.624534.00388.43214.754119.045144.583
us-gaap:ProfitLoss ▃▂▄▂▂▃▂▂▄▂▁▃▃▃▂▂▂▂▂▂▃▂▃▄▁▂▂▃▅▃▂▂▂▂▂▂▃▂▂▂█▃▂▃▃117.134-3.855200.3420.67766.627127.11424.25540.722173.74152.769-58.3299.454115.899113.82338.33545.79516.0150.92453.9743.343149.09532.503114.249176.753-29.17955.63665.32573.594250.332156.61244.36245.33631.24830.33727.45728.63118.45735.15717.55516.488549.18793.89417.959124.566150.499
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
us-gaap:NetCashProvidedByUsedInInvestingActivities ▆▄▆▄▆▄▅▅▄▄▅▅▄▅▅▅▄▅▄▅█▅▄▁▃▅▄▃▄▄▄▄▅▄▄▄▄▄▄▄▄▅▄▄▅621.3420.181681.407-28.796533.237-129.418355.394225.504-174.561-291.843181.43232.168-187.938456.00282.19162.732-293.57729.804-282.603278.4261787.89338.857-279.485-1728.493-488.23230.29728.428-507.222-246.24-71.801-385.97-195.943127.968-174.49-341.217-271.129-263.855-294.192-238.078-436.786-95.73230.999-156.175-71.909307.142
 us-gaap:PaymentsToAcquireRealEstate us-gaap:BusinessAcquisition,us-gaap:SubsequentEventType slg:FifthAvenue461,us-gaap:SubsequentEventNANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:PaymentsToAcquireInvestments NANANA88.22342.2223.374NA32.47593.442430.034NA48.734374.147229.428NA81.147452.124402.453422.61327.607110.077117.119295.68274.041212.796174.42196.087164.273106.266150.464161.708115.55282.873195.004NANANANANANANANANANANA
 us-gaap:PaymentsToAcquireInvestments us-gaap:ConsolidatedEntities srt:SubsidiariesNANANA88.22342.2223.374NA32.47593.442430.034NA48.734374.147229.428NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
us-gaap:NetCashProvidedByUsedInFinancingActivities ▃▅▃▃▄▆▄▄▅▅▄▄▅▄▄▄▅▅▅▄▁▄▅█▅▄▅▆▅▅▅▅▄▅▅▅▅▅▅▆▅▅▅▅▄-791.108-9.971-839.354-871.676-235.255466.984-407.548-331.625-35.605246.128-284.901-424.88937.987-422.309-327.543-295.107-101.05642.62930.228-284.17-2087.157-392.14187.0391667.417230.856-271.895-113.714351.995-81.233224.123307.815109.106-260.066102.085281.051108.672245.885232.834-93.399380.214154.913-209.629151.193-98.26-221.191
 us-gaap:NetCashProvidedByUsedInFinancingActivities us-gaap:ConsolidatedEntities srt:Subsidiaries▁▆▁▁▄█▃▄▅▇▄▃▆▃-791.108-9.971-839.354-871.676-235.255466.984-407.548-331.625-35.605246.128-284.901-424.88937.987-422.309NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:PaymentsOfDividends ▆▇▇▇▇█▇▇▇▇▇▇▇█████▇▇▇▇▆▆▆▆▅▅▅▅▃▃▄▃▂▃▃▂▁▁▁▁▁▁▁68.60169.77269.84970.67373.81279.66275.58276.34477.06177.39976.22376.30878.9781.72981.84283.02384.49984.17979.27878.56778.13178.10365.45864.6164.40762.90352.06751.96451.29151.65235.21533.65840.94338.59129.96632.11730.70228.45316.18216.02215.9815.68215.37715.38415.388
us-gaap:PaymentsForRepurchaseOfCommonStock ▂▂▃▁▃▄▄▂▂▂▄▂▆▇█▃▄▁▁▁▁▁94.57784.089146.49129.944132.472219.576209.39465.69275.0734.243219.46835.377342.017382.679456.311138.392211.4970.1020.00.00.00.0NANANANANANANANANANANANA2.9530.039NANA1.1730.116NANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30

Common Stock Value

us-gaap:CommonStockValue

us-gaap:CommonStockValue


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value690000.0705000.0716000.0741000.0748000.0776000.0803000.0826000.0835000.0843000.0847000.0867000.0868000.0902000.0939000.0985000.0995000.01019000.01017000.01013000.01003000.01002000.01001000.01034000.01033000.01032000.01010000.0996000.0993000.0990000.0986000.0959000.0955000.0953000.0950000.0940000.0936000.0925000.0892000.0892000.0878000.0844000.0817000.0809000.0
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Shares Outstanding

us-gaap:SharesOutstanding us-gaap:StatementEquityComponents

us-gaap:SharesOutstanding

us-gaap:CommonStock


Shares
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302010-12-312009-12-312008-12-31
Value6769687373767981828383858589929798100100100100100999999999795959594929191919089888585787757
Percentage of SharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Common Stock Shares Issued

us-gaap:CommonStockSharesIssued

us-gaap:CommonStockSharesIssued


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value68706974747780828384848686909398991011011001001001001031031031009999989895959594939392898987848180
Percentage of CommonStockSharesIssued100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Common Stock Shares Outstanding

us-gaap:CommonStockSharesOutstanding

us-gaap:CommonStockSharesOutstanding


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-06-302011-03-312010-12-312009-12-31
Value687069747477808283848486869093989910110110010010010010310310310099999898959595949393928987848180
Percentage of CommonStockSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Diluted Shares Outstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding


Weighted
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value737477808286878790929510210410510510410410399103999998959494939390888681797979
Percentage of WeightedAverageNumberOfDilutedSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Shares Outstanding Basic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic


Weighted
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value68697375778282838587909799100100100100999998959595919191908986858379787877
Percentage of WeightedAverageNumberOfSharesOutstandingBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Basic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareBasic


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1.52-0.112.440.190.741.470.210.41.940.52-0.731.031.191.120.290.40.080.110.440.341.330.231.021.64-0.390.440.590.682.471.540.390.40.090.210.230.091.150.290.030.086.31.020.091.431.760.19
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Diluted

us-gaap:EarningsPerShareDiluted

us-gaap:EarningsPerShareDiluted


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1.51-0.112.430.190.741.470.210.41.940.52-0.731.031.191.120.290.40.080.110.440.341.330.231.021.64-0.390.440.590.682.461.530.390.40.090.210.230.091.140.290.030.086.261.010.091.421.750.19
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Allocated Share Based Compensation Expense

us-gaap:AllocatedShareBasedCompensationExpense us-gaap:AwardType

us-gaap:AllocatedShareBasedCompensationExpense

slg:RestrictedStockAwards


Allocated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value2.1918062.0671252.3664682.8373052.7619052.9297813.4226273.1374542.9203273.4118413.1898083.1163753.1349752.4227042.4734242.3809261.8781671.9033651.355882.0165541.8775511.8511671.8751761.9368532.3900962.5896542.3376022.3406672.2916041.4502121.5071161.4642231.642012
Percentage of AllocatedShareBasedCompensationExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating602.1531.40.0489.2426.2587.10.0516.0123.0588.2785.7895.5992.1680.5629.4457.00.02883.9129.6233.10.0238.6258.3297.10.0331.2423.5440.00.0257.6320.7323.20.0
Percentage of InterestIncomeOperating slg:RestrictedStockAwards0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:PerformanceShares


Allocated
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-30
Value9.19.16.46.77.33.03.08.02.3
Percentage of AllocatedShareBasedCompensationExpense415.2440.2225.6242.6249.295.6102.7234.572.1
Percentage of InterestIncomeOperating2500.02339.31103.41034.01462.9493.4126.41379.3566.5
Percentage of InterestIncomeOperating us-gaap:PerformanceShares0.00.00.00.00.00.00.00.00.0

us-gaap:AllocatedShareBasedCompensationExpense us-gaap:AwardType, us-gaap:PlanName

us-gaap:EmployeeStockOption, slg:ThirdAmendmentandRestated2005StockOptionandIncentivePlan


Allocated
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-0.030.00.010.020.70.60.60.61.11.11.61.61.92.01.90.02.52.51.92.02.21.91.92.02.12.02.02.1
Percentage of AllocatedShareBasedCompensationExpense-1.30.00.40.720.519.120.517.60.034.551.351.00.082.676.80.0133.1131.3140.199.2117.2102.6101.3103.387.977.285.689.7
Percentage of InterestIncomeOperating0.00.01.54.00.098.725.3103.40.0270.9459.8506.30.0561.8483.50.00.03787.9181.6231.20.0244.8261.7306.70.0255.8362.3394.7
Percentage of InterestIncomeOperating us-gaap:EmployeeStockOption slg:ThirdAmendmentandRestated2005StockOptionandIncentivePlan0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AllocatedShareBasedCompensationExpense us-gaap:PlanName

slg:DeferredStockCompensationPlanForDirectors


Allocated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-30
Value0.21.80.20.20.21.80.20.20.21.90.20.10.12.20.20.10.21.90.20.10.21.60.10.10.31.30.10.10.1
Percentage of AllocatedShareBasedCompensationExpense9.187.18.57.07.261.45.86.46.855.70.03.13.270.20.04.18.179.810.65.314.879.35.35.416.067.14.23.94.3
Percentage of InterestIncomeOperating54.9462.70.034.530.9360.70.032.98.4327.60.024.628.7696.20.028.150.9364.70.0151.519.1185.00.012.941.3199.40.012.818.1
Percentage of InterestIncomeOperating slg:DeferredStockCompensationPlanForDirectors0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Comprehensive Income Net Of Tax

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:ComprehensiveIncomeNetOfTax


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value6144183235866322514028-78.6739511111536429.8029.463834013718112162-34.464425671247150444034292714106376.371152598
Percentage of ComprehensiveIncomeNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating16786.511471.50.04097.99055.213257.70.04137.85916.24899.50.023552.731995.136542.10.011920.82494.11816.30.061324.213179.52137.10.020938.3-4747.16470.10.09172.144919.428226.90.07129.07431.96575.30.03828.826570.39089.50.02299.697663.020222.7

us-gaap:ComprehensiveIncomeNetOfTax us-gaap:ConsolidatedEntities

srt:Subsidiaries


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value6945195266475362915133-79.271103119123
Percentage of ComprehensiveIncomeNetOfTax113.3103.1106.4111.2109.2113.4111.3117.7107.9117.6100.8108.0107.6107.0
Percentage of InterestIncomeOperating19013.211823.70.04557.69892.115034.90.04869.96381.25761.90.025435.234418.439112.0
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value6647209276571362814832-80.652103120124424513-4.901914514923121171-28.233506177259156484439332727114391313540103
Percentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating18221.712120.80.04683.610035.314397.80.04667.46238.15629.80.025453.434538.539370.60.012815.23500.8-940.70.069613.614312.22740.80.022119.5-3888.87761.70.09847.446971.729494.20.07936.88340.27475.90.07176.928495.59522.40.02651.3100449.121366.8

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest us-gaap:ConsolidatedEntities

srt:Subsidiaries


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value6647209276571362814832-80.652103120124
Percentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating18221.712120.80.04683.610035.314397.80.04667.46238.15629.80.025453.434538.539370.6
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Costs And Expenses

us-gaap:CostsAndExpenses

us-gaap:CostsAndExpenses


Costs
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value434245405359585756565975707478797579767870767172707374776973728368737169626061585256
Percentage of CostsAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating12055.810869.97915.56311.310794.89843.32456.59947.914003.016160.118918.421327.818028.514300.60.0120340.97201.19193.10.010135.19657.611775.60.09221.412803.413813.20.013725.014772.816254.50.021756.517186.817870.50.013521.911599.612433.00.012148.110465.90.0

us-gaap:CostsAndExpenses us-gaap:ConsolidatedEntities

srt:Subsidiaries


Costs
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value4342454053595857565659
Percentage of CostsAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating12055.810869.97915.56311.310794.89843.32456.59947.914003.016160.118918.4
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CostsAndExpenses us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Costs
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value424648443551495048545356505941383938
Percentage of CostsAndExpenses96.6109.30.097.386.495.80.084.883.293.80.099.089.5100.00.050.155.352.1
Percentage of InterestIncomeOperating11651.111885.10.07698.35453.410338.70.08348.52043.69331.70.013868.014470.118915.50.010689.69961.17446.1
Percentage of InterestIncomeOperating us-gaap:CorporateJointVenture0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Gains Losses On Extinguishment Of Debt

us-gaap:GainsLossesOnExtinguishmentOfDebt us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:GainsLossesOnExtinguishmentOfDebt

us-gaap:CorporateJointVenture


Gains
Period End2021-06-302019-09-302018-09-302017-09-30
Value-1.326-1.0310.0-7.638
Percentage of GainsLossesOnExtinguishmentOfDebt100.0100.00.0100.0
Percentage of InterestIncomeOperating-364.3-169.60.0-2145.5
Percentage of InterestIncomeOperating us-gaap:CorporateJointVenture0.00.00.00.0

Income Tax Expense Benefit

us-gaap:IncomeTaxExpenseBenefit

us-gaap:IncomeTaxExpenseBenefit


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-31
Value800000.0700000.0-800000.00900000.01100000.01000000.01000000.0700000.0800000.0800000.0300000.01100000.0500000.01500000.0100000.02200000.0900000.0900000.0300000.01200000.0600000.01100000.01100000.0300000.01200000.01600000.02100000.02900000.0-1600000.02100000.02300000.01600000.0-200000.00100000.00-200000.00
Percentage of IncomeTaxExpenseBenefit100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.00.0100.00.0
Percentage of InterestIncomeOperating219.8179.90.00.0138.9220.40.0164.529.5137.90.073.9316.1158.20.028.1559.80.01363.628.7138.70.0141.8151.546.00.0204.6380.4545.10.0373.0489.4353.20.00.024.90.00.00.0

Interest Expense

us-gaap:InterestExpense

us-gaap:InterestExpense


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value3839414244566163606028646154397271727178951028884767681837980838383818286828076756964615657
Percentage of InterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating10577.210248.80.07344.06934.711385.40.010461.72558.810484.50.015782.817687.617379.10.020466.018318.613900.60.0119265.29136.511809.80.010942.910533.311726.80.010634.014341.115171.40.014837.717818.318055.00.022335.220630.419645.60.014860.912923.413350.70.011907.911397.8

us-gaap:InterestExpense us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Interest
Period End2021-06-302021-03-312020-06-302020-03-31
Value79787986
Percentage of InterestExpense205.5197.5177.2151.9
Percentage of InterestIncomeOperating21738.720244.012289.817299.4
Percentage of InterestIncomeOperating us-gaap:CorporateJointVenture0.00.00.00.0

Interest Income Expense Net

us-gaap:InterestIncomeExpenseNet

us-gaap:InterestIncomeExpenseNet


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-18.96-23.388-25.579-23.536-30.07-37.494336-48.112-47.16-50.525365-55.168-53.611-47.916453-65.634646564728994-88.176-84.141-75.746-75.807-80.976-82.376-78.611-80.18-82.795-82.973-83.276-81.336-82.277-85.828-82.327-80.137492-74.603-68.173-64.266
Percentage of InterestIncomeExpenseNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating-5208.8-6012.30.0-4057.9-4640.4-7513.80.0-7913.2-1986.5-8711.20.0-13588.2-15405.5-15163.30.0-18436.516502.812595.40.0109947.08517.110944.70.0-10842.9-10433.3-11626.80.0-10534.0-14241.1-15071.40.0-14737.7-17718.3-17955.00.0-22235.2-20530.4-19545.60.0-14599.4-12671.6-13250.7

Interest Income Operating

us-gaap:InterestIncomeOperating

us-gaap:InterestIncomeOperating


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value364000.0389000.0452000.0580000.0648000.0499000.0561000.0608000.02374000.0580000.0887000.0406000.0348000.0316000.0315000.0356000.0393000.0521000.0820000.066000.01046000.0865000.0795000.0776000.0726000.0652000.0637000.0782000.0552000.0532000.0576000.0563000.0470000.0453000.0422000.0386000.0401000.0410000.0469000.0511000.0538000.0485000.0796000.0478000.0504000.0
Percentage of InterestIncomeOperating100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value109-3.7261741760118213616447-57.4829110710531421115473713726105167-35.368476068239149404027262725110331014534881411914422
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating29964.0-957.838658.83034.09287.223755.33773.46068.36943.68194.8-6480.522647.030831.333387.310069.511968.33043.02896.25823.557560.613116.13116.613212.721571.6-4871.67210.99501.68750.143347.628163.27093.27240.35837.25809.36484.16646.927577.18097.12207.02861.899257.118233.41853.524904.828687.10.0

us-gaap:NetIncomeLoss us-gaap:ConsolidatedEntities

srt:Subsidiaries


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value115-4.2021841863124223817349-60.9219611211033441215
Percentage of NetIncomeLoss105.8112.8105.7104.6105.1105.2104.7104.7105.0104.8106.0105.2105.2105.0104.1104.3103.5103.2
Percentage of InterestIncomeOperating31689.8-1080.240858.63172.29761.024998.23950.66351.07293.68587.6-6868.223828.632436.535055.710478.412477.23149.62987.5
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Income Loss Attributable To Noncontrolling Interest

us-gaap:NetIncomeLossAttributableToNoncontrollingInterest

us-gaap:NetIncomeLossAttributableToNoncontrollingInterest


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value8.065-0.129253.086.4468.5753.0863.8278.9015.239-0.8387.5078.6068.3196.6163.1884.056-14.1656.2175.353115.5449.2089.3576.1898.6214.8025.168116.7843.5054.5733.8134.0210.0942.9737.8732.3567.2021.864
Percentage of NetIncomeLossAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating2215.7-33.25664.2531.0994.81718.4550.1629.4374.9903.3-94.51849.02473.02632.62100.3895.51032.1-2718.8758.28110.61137.8640.91158.21205.8852.51322.2753.8660.92002.41275.2608.5812.3811.3887.622.3770.21963.3574.61535.6364.8

Net Income Loss Available To Common Stockholders Basic

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value105-7.4641711356114173316143-61.2198810310127388.22211443413323101163-39.10643566423514637378.27618197.732103252.8087.079526807.20911113715
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating28937.4-1918.837832.12389.58710.523006.23107.35453.56786.17550.3-6901.821726.429757.532204.48883.210918.32092.12178.75367.851897.012758.82684.512742.521089.9-5386.56637.68914.88272.142670.527460.56444.46576.41760.94174.24728.92003.125695.86160.0598.71385.397854.616677.7905.723326.427190.10.0

Net Income Loss Available To Common Stockholders Diluted

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value111-7.941801459121183416946-64.6599310910729408.64111453513924105170-39.10645596724415038388.5219208.299106263.4927.248538827.239113139
Percentage of NetIncomeLossAvailableToCommonStockholdersDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating30663.2-2041.140031.92527.89184.324249.13281.15736.27136.27943.1-7289.622907.931362.633872.89292.111427.22198.72270.15607.454416.713292.82791.113237.021923.5-5386.56904.99300.28609.244236.628349.46637.86773.51812.84296.74899.82150.026548.96376.6744.61418.4100071.217059.6909.423700.027679.6

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted us-gaap:ConsolidatedEntities

srt:Subsidiaries


Net
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value111-7.941459121341694693109107
Percentage of NetIncomeLossAvailableToCommonStockholdersDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating30663.2-2041.12527.89184.324249.15736.27136.27943.122907.931362.633872.8
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.0

Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value-51.313518.4846.099-3.59-50.73512-12.574-26.22-20.884-22.4313.919
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating-14097.013178.11877.01051.6-554.0-10167.32239.2-2068.1-1104.5-3600.7-2528.9965.3

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax us-gaap:ConsolidatedEntities

srt:Subsidiaries


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value-51.313518.4846.099-3.59-50.73512-12.574-26.22-20.884-22.4313.919
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating-14097.013178.11877.01051.6-554.0-10167.32239.2-2068.1-1104.5-3600.7-2528.9965.3
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.0

Other Comprehensive Income Loss Net Of Tax

us-gaap:OtherComprehensiveIncomeLossNetOfTax

us-gaap:OtherComprehensiveIncomeLossNetOfTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value-50.807519.3186.488-1.598-55.26912-12.344-25.648-20.116-22.3323.8874.295104.628-0.173-2.257-5.825372.6020.611-8.7957.354-5.1060.946-5.03-4.2563.4138.9520.2974.159-0.6527.9513.529-0.298-0.927-4.193.885-4.101-2.94
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating-13958.013111.82061.51118.6-246.6-11076.02181.8-2030.3-1080.4-3468.3-2517.7957.41234.23350.61469.2-48.6-574.3-1118.04605.73942.458.4-1016.8925.0-658.0130.3-771.5-668.1436.41621.755.8722.0-115.81691.7779.0-70.6-240.2-1044.9947.6-874.4-575.3

us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:ConsolidatedEntities

srt:Subsidiaries


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-50.807519.3186.488-1.598-55.26912-12.344-25.648-20.116-22.3323.8874.29510
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating-13958.013111.82061.51118.6-246.6-11076.02181.8-2030.3-1080.4-3468.3-2517.7957.41234.23350.6
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Other Income

us-gaap:OtherIncome

us-gaap:OtherIncome


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value13182531175315141614117.70213149.3427.26615116.2116.6731079.4891316189.9327.2231122143.6529.8775.7265.7749.8049.2726.28210126.0779.9327.249118.0658.8778.199
Percentage of OtherIncome100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating3678.34817.55709.75403.62757.710649.12710.72317.1692.82432.11303.81897.03856.94632.02965.72041.03944.32219.0757.410110.610322.71097.01636.12064.32513.81523.31133.91430.44121.42741.0634.01754.41218.31274.62323.22402.11566.62531.02606.01189.21846.11494.61385.61687.21761.30.0

us-gaap:OtherIncome us-gaap:ConsolidatedEntities

srt:Subsidiaries


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value13182531175315141614117.7021314
Percentage of OtherIncome100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating3678.34817.55709.75403.62757.710649.12710.72317.1692.82432.11303.81897.03856.94632.0
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Profit Loss

us-gaap:ProfitLoss

us-gaap:ProfitLoss


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value117-3.8552002066127244017352-58.32991151133845160.924534314932114176-29.179556573250156444531302728118351716549931712415026
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating32179.7-991.044323.03565.010281.925473.74323.56697.77318.59098.1-6575.024496.133304.336019.912169.812863.84075.1177.46581.765671.214253.83757.614370.922777.4-4019.18533.110255.19411.045350.029438.37701.78052.66648.56696.96506.47417.129540.48574.93743.13226.6102079.419359.62256.226059.829860.90.0

us-gaap:ProfitLoss us-gaap:ConsolidatedEntities

srt:Subsidiaries


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value117-3.8552002066127244017352-58.3299115113
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating32179.7-991.044323.03565.010281.925473.74323.56697.77318.59098.1-6575.024496.133304.336019.9
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ProfitLoss us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Profit
Period End2021-06-302021-03-312020-06-302020-03-31
Value-17.495-4.94-5.056-18.525
Percentage of ProfitLoss-14.9128.1-7.6-14.6
Percentage of InterestIncomeOperating-4806.3-1269.9-780.2-3712.4
Percentage of InterestIncomeOperating us-gaap:CorporateJointVenture0.00.00.00.0

Revenue From Contract With Customer Including Assessed Tax

us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService, us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax

us-gaap:ManagementServiceBase, us-gaap:CorporateJointVenture


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value4.22.49.72.21.72.24.22.43.92.54.92.43.03.8
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating1153.8617.02146.0379.3262.3440.9748.7394.7164.3431.0552.4591.1862.11202.5
Percentage of InterestIncomeOperating us-gaap:ManagementServiceBase us-gaap:CorporateJointVenture0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Revenues

us-gaap:Revenues

us-gaap:Revenues


Revenues
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value218226234249253314308313313304317307301301361374398377374416617455425432409396386390387381374363365369350361349339328308300334262319251250
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating59919.558123.951968.643076.639151.162986.654916.651584.513185.552457.835742.575750.086527.695473.1114711.7105224.7101310.472434.045639.3631334.859045.352652.553508.255678.656346.360782.160695.049907.270149.871640.665051.964611.977690.481671.383112.193637.687033.782729.870123.060386.355883.868932.433013.266768.049915.10.0

us-gaap:Revenues us-gaap:ConsolidatedEntities

srt:Subsidiaries


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value218226234249253314308313313304317307301301361374398377
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating59919.558123.951968.643076.639151.162986.654916.651584.513185.552457.835742.575750.086527.695473.1114711.7105224.7101310.472434.0
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:Revenues us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, slg:RealEstateSegment


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-30
Value198206216226213275265262261254259258251256316326337330329335569400380382363354345346340
Percentage of Revenues90.891.592.090.884.387.786.283.683.583.681.784.183.685.087.587.284.887.788.180.692.388.089.588.689.089.489.488.788.0
Percentage of InterestIncomeOperating54395.653169.447831.639113.132987.055264.547354.743111.011011.243831.729209.063686.772368.781140.8100384.891792.185885.063498.840224.0508563.654476.546324.547905.749321.950121.654329.854251.044284.561760.5
Percentage of InterestIncomeOperating us-gaap:OperatingSegments slg:RealEstateSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, slg:StructuredFinanceSegment


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-30
Value2019182239384251515057484945454760464481475444494542414339
Percentage of Revenues9.28.58.09.215.712.313.816.416.516.418.315.916.415.012.512.815.212.311.919.47.712.010.511.411.010.610.611.310.3
Percentage of InterestIncomeOperating5523.94954.54136.93963.46164.07722.07561.98473.52174.38626.06533.512063.314158.914332.314327.013432.615425.48935.15415.2122771.24568.86328.05602.56356.76224.76452.36444.05622.67194.6
Percentage of InterestIncomeOperating us-gaap:OperatingSegments slg:StructuredFinanceSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:Revenues us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Revenuesus-gaap:
Period End2021-06-302021-03-312020-06-302020-03-31
Value289301271282
Percentage of Revenues132.6133.4107.089.9
Percentage of InterestIncomeOperating79447.377517.041900.956617.2
Percentage of InterestIncomeOperating us-gaap:CorporateJointVenture0.00.00.00.0

Selling General And Administrative Expense

us-gaap:SellingGeneralAndAdministrativeExpense

us-gaap:SellingGeneralAndAdministrativeExpense


Selling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value22222523231925232525262022232823242425252424222323252222232322202121212020201818222020181818
Percentage of SellingGeneralAndAdministrativeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating6061.55883.05562.84069.33628.13921.84558.83921.21073.34479.12934.65072.46459.57445.68932.16731.26172.04634.03146.338636.42342.32778.32863.03025.13195.63905.53565.12896.34324.64371.63948.33706.74577.44650.65064.25324.15167.34925.93993.23698.64173.64128.02599.93864.93646.60.0

us-gaap:SellingGeneralAndAdministrativeExpense us-gaap:ConsolidatedEntities

srt:Subsidiaries


Selling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value2222252323192523252526202223
Percentage of SellingGeneralAndAdministrativeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating6061.55883.05562.84069.33628.13921.84558.83921.21073.34479.12934.65072.46459.57445.6
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Assets

us-gaap:Assets

us-gaap:Assets


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1116612044117071232413071132201276613294136291338512751134551371313380139821510915309158771585715790175441958519857194901726617080170961723716717153631495914574144011454314387142841413913761134831316212644114421130010487
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:ConsolidatedEntities

srt:Subsidiaries


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value111661204411707123241307113220127661329413629133851275113982
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets srt:Subsidiaries100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, slg:RealEstateSegment


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302014-12-31
Value1004210896105791107911755113451106311216113081094310481112561124911144116961293913161139121386813992158651819518175179661556215671
Percentage of Assets89.990.590.489.989.985.886.784.483.081.882.283.782.083.383.685.686.087.687.588.690.492.991.592.290.191.7
Percentage of Assets89.990.590.489.989.985.886.784.483.081.882.283.782.083.383.685.686.087.687.588.690.492.991.592.290.191.7
Percentage of Assets us-gaap:OperatingSegments slg:RealEstateSegment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, slg:StructuredFinanceSegment


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302014-12-31
Value11231147112712441316187517032078232124422269219824632236228621702148196519891798167813901682152317041424
Percentage of Assets10.19.59.610.110.114.213.315.617.018.217.816.318.016.716.414.414.012.412.511.49.67.18.57.89.98.3
Percentage of Assets10.19.59.610.110.114.213.315.617.018.217.816.318.016.716.414.414.012.412.511.49.67.18.57.89.98.3
Percentage of Assets us-gaap:OperatingSegments slg:StructuredFinanceSegment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312019-12-31
Value18162179231890617096
Percentage of Assets162.7148.8161.5133.9
Percentage of Assets162.7148.8161.5133.9
Percentage of Assets us-gaap:CorporateJointVenture100.0100.0100.0100.0

Liabilities

us-gaap:Liabilities

us-gaap:Liabilities


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value57986535621166347281725165556843706268436115641866836065662971537172738073307275900811179114311111291868927909694199016789776277508738573687218711069986822683366356224568258185489
Percentage of Liabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets51.954.353.153.855.754.951.451.551.851.148.047.748.745.347.447.346.846.546.246.151.357.157.657.053.252.353.254.653.951.451.051.551.350.750.249.849.549.650.750.449.249.751.552.3

us-gaap:Liabilities us-gaap:ConsolidatedEntities

srt:Subsidiaries


Liabilitiesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value579865356211663472817251655568437062684361156629
Percentage of Liabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets51.954.353.153.855.754.951.451.551.851.148.047.4
Percentage of Assets srt:Subsidiaries51.954.353.153.855.754.951.451.551.851.148.047.4

Liabilities And Stockholders Equity

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:LiabilitiesAndStockholdersEquity


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1116612044117071232413071132201276613294136291338512751134551371313380139821510915309158771585715790175441958519857194901726617080170961723716717153631495914574144011454314387142841413913761134831316212644114421130010487
Percentage of LiabilitiesAndStockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LiabilitiesAndStockholdersEquity us-gaap:ConsolidatedEntities

srt:Subsidiaries


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value111661204411707123241307113220127661329413629133851275113982
Percentage of LiabilitiesAndStockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets srt:Subsidiaries100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LiabilitiesAndStockholdersEquity us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Liabilities
Period End2021-06-302021-03-312020-12-312019-12-31
Value18162179231890617096
Percentage of LiabilitiesAndStockholdersEquity162.7148.8161.5133.9
Percentage of Assets162.7148.8161.5133.9
Percentage of Assets us-gaap:CorporateJointVenture100.0100.0100.0100.0

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value47894911490950565119526354415692580957975901621461906487622568176935726373247293731872687287723871157148693768446780662565256281623464176419637163216162597560285869509548794388
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets42.940.841.941.039.239.842.642.842.643.346.346.245.148.544.545.145.345.746.246.241.737.136.737.141.241.940.639.740.643.143.643.143.344.144.644.644.744.844.345.846.444.543.241.8

Cash And Cash Equivalents At Carrying Value

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:CashAndCashEquivalentsAtCarryingValue


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value218304266221101555416612114814412916028728812724127046827940527631625524421533028125330844720620919822018916225613313839439023433227033916734372645
Percentage of CashAndCashEquivalentsAtCarryingValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.02.52.31.87.84.21.30.91.11.11.01.22.12.20.91.61.82.91.82.61.61.61.31.31.31.91.61.51.82.91.41.41.41.51.31.11.81.01.03.03.12.02.90.00.00.03.30.00.0

us-gaap:CashAndCashEquivalentsAtCarryingValue us-gaap:ConsolidatedEntities

srt:Subsidiaries


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value2183042662211015554166121148144129160287288127
Percentage of CashAndCashEquivalentsAtCarryingValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.02.52.31.87.84.21.30.91.11.11.01.22.12.20.9
Percentage of Assets srt:Subsidiaries2.02.52.31.87.84.21.30.91.11.11.00.00.00.00.9

us-gaap:CashAndCashEquivalentsAtCarryingValue us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-31
Value1279317357326312329336299319370381350434452494328
Percentage of CashAndCashEquivalentsAtCarryingValue585.8104.2134.2147.530.859.4202.4246.2214.4256.9294.5218.9151.2156.7387.0117.5
Percentage of Assets11.52.63.02.62.42.52.62.32.32.83.02.63.23.43.52.1
Percentage of Assets us-gaap:CorporateJointVenture7.01.81.90.00.00.02.00.00.00.00.00.00.00.00.00.0

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value3164013723041101621241216241295279258379378250349380539369
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.83.33.22.58.44.71.91.61.82.22.21.92.82.81.82.32.53.42.3

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents us-gaap:ConsolidatedEntities

srt:Subsidiaries


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-31
Value3164013723041101621241216241295279258379378250369488
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets2.83.33.22.58.44.71.91.61.82.22.21.92.82.81.82.32.5
Percentage of Assets srt:Subsidiaries2.83.33.22.58.44.71.91.61.82.22.20.00.00.01.80.00.0

Land

us-gaap:Land

us-gaap:Land


Land
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value14031445131516391625166217511860192917751774182718932098235729172936329533093347410841154779468937563830384438333466311230322868286628862886293728722816268425812472197417501379
Percentage of Land100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets12.612.011.213.312.412.613.714.014.213.313.913.613.815.716.919.319.220.820.921.223.421.024.124.121.822.422.522.220.720.320.319.719.919.820.120.620.320.519.919.619.617.315.513.1

us-gaap:Land slg:InvestmentsByConsolidatedAndNonconsolidatedEntities

us-gaap:VariableInterestEntityPrimaryBeneficiary


Landslg:
Period End2020-09-302020-06-302020-03-312019-12-31
Value375355199205
Percentage of Land22.921.812.011.7
Percentage of Assets3.12.71.51.6
Percentage of Assets us-gaap:VariableInterestEntityPrimaryBeneficiary0.00.00.00.0

us-gaap:Land slg:InvestmentsByConsolidatedAndNonconsolidatedEntities, us-gaap:ConsolidatedEntities

us-gaap:VariableInterestEntityPrimaryBeneficiary, srt:Subsidiaries


Landslg:
Period End2020-09-302020-06-302020-03-312019-12-31
Value375355199205
Percentage of Land22.921.812.011.7
Percentage of Assets3.12.71.51.6
Percentage of Assets us-gaap:VariableInterestEntityPrimaryBeneficiary srt:Subsidiaries0.00.00.00.0

us-gaap:Land us-gaap:ConsolidatedEntities

srt:Subsidiaries


Landus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value140314451315163916251662175118601929177517742357
Percentage of Land100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets12.612.011.213.312.412.613.714.014.213.313.916.9
Percentage of Assets srt:Subsidiaries12.612.011.213.312.412.613.714.014.213.313.916.9

us-gaap:VariableInterestEntityPrimaryBeneficiary


Landus-gaap:
Period End2021-06-302021-03-312020-12-312019-12-31
Value17917941205
Percentage of Land12.812.43.111.7
Percentage of Assets1.61.50.41.6
Percentage of Assets us-gaap:VariableInterestEntityPrimaryBeneficiary0.00.00.00.0

Finite Lived Intangible Assets Net

us-gaap:FiniteLivedIntangibleAssetsNet

us-gaap:FiniteLivedIntangibleAssetsNet


Finite
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value3035251619222630352225212341487685232240227602615535546541559281303319414403406435445462492500507480512409624
Percentage of FiniteLivedIntangibleAssetsNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.30.30.20.10.10.20.20.20.30.20.20.20.20.30.30.50.61.51.51.43.43.12.72.83.13.31.61.81.92.72.72.83.03.13.23.43.53.73.63.93.25.5

Operating Lease Right Of Use Asset

us-gaap:OperatingLeaseRightOfUseAsset

us-gaap:OperatingLeaseRightOfUseAsset


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value5025023673813813813963963963960.0
Percentage of OperatingLeaseRightOfUseAsset100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets4.54.23.13.12.92.93.13.02.93.00.0

us-gaap:OperatingLeaseRightOfUseAsset us-gaap:ConsolidatedEntities

srt:Subsidiaries


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value5025023673813813813963963963960.0
Percentage of OperatingLeaseRightOfUseAsset100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets4.54.23.13.12.92.93.13.02.93.00.0
Percentage of Assets srt:Subsidiaries4.54.23.13.12.92.93.13.02.93.00.0

Other Assets

us-gaap:OtherAssets

us-gaap:OtherAssets


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value33644544851428635333227123532429530129036031039536058461462097910558509121144978647729679815750729699722718774784796737753575693819290
Percentage of OtherAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.03.73.84.22.22.72.62.01.72.42.32.22.12.72.22.62.43.73.93.95.65.44.34.76.65.73.84.24.15.35.05.04.95.05.05.45.65.85.55.74.56.17.32.8

us-gaap:OtherAssets slg:InvestmentsByConsolidatedAndNonconsolidatedEntities

us-gaap:VariableInterestEntityPrimaryBeneficiary


Other
Period End2020-09-302020-06-302020-03-312019-12-31
Value322371179169
Percentage of OtherAssets62.7129.650.750.9
Percentage of Assets2.62.81.41.3
Percentage of Assets us-gaap:VariableInterestEntityPrimaryBeneficiary0.00.00.00.0

us-gaap:OtherAssets slg:InvestmentsByConsolidatedAndNonconsolidatedEntities, us-gaap:ConsolidatedEntities

us-gaap:VariableInterestEntityPrimaryBeneficiary, srt:Subsidiaries


Other
Period End2020-09-302020-06-302020-03-312019-12-31
Value322371179169
Percentage of OtherAssets62.7129.650.750.9
Percentage of Assets2.62.81.41.3
Percentage of Assets us-gaap:VariableInterestEntityPrimaryBeneficiary srt:Subsidiaries0.00.00.00.0

us-gaap:OtherAssets us-gaap:ConsolidatedEntities

srt:Subsidiaries


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value336445448514286353332271235324295310
Percentage of OtherAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.03.73.84.22.22.72.62.01.72.42.32.2
Percentage of Assets srt:Subsidiaries3.03.73.84.22.22.72.62.01.72.42.32.2

us-gaap:VariableInterestEntityPrimaryBeneficiary


Other
Period End2021-06-302021-03-312020-12-312019-12-31
Value291297289169
Percentage of OtherAssets86.566.764.650.9
Percentage of Assets2.62.52.51.3
Percentage of Assets us-gaap:VariableInterestEntityPrimaryBeneficiary0.00.00.00.0

us-gaap:OtherAssets us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-31
Value186919502001194019471997203920842093219121872235225423611407683
Percentage of OtherAssets555.1437.7446.6376.9679.3564.8612.8767.8889.5675.1739.7742.3775.6654.9453.1111.3
Percentage of Assets16.716.217.115.714.915.116.015.715.416.417.216.616.417.610.14.3
Percentage of Assets us-gaap:CorporateJointVenture10.310.910.60.00.00.011.90.00.00.00.00.00.00.00.00.0

Long Term Debt

us-gaap:LongTermDebt

us-gaap:LongTermDebt


Long
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value197921831961283764776435666465686519808110084104581015784068122846887758399724069676869-6721.936-6678.073-6520.42-6388.277-6278.024-6081.046-6094.496-5886.441-5597.585
Percentage of LongTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets16.917.115.420.342.942.042.041.441.346.151.552.752.148.747.649.550.950.247.146.647.1-46.7-45.9-45.3-44.7-44.4-44.2-45.2-44.7-44.3

us-gaap:LongTermDebt us-gaap:DebtInstrument

slg:TermLoan


Long
Period End2021-06-302021-03-312020-09-302020-06-302017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-31
Value150015001500150011831183118311831183933933933933833833833
Percentage of LongTermDebt0.00.00.00.018.318.417.818.018.111.59.38.99.29.910.39.8
Percentage of Assets13.412.512.211.57.87.77.57.57.55.34.84.74.84.84.94.9
Percentage of Assets slg:TermLoan0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:LongTermDebt us-gaap:DebtInstrument, us-gaap:LongtermDebtType

slg:CreditFacility2012, us-gaap:LineOfCredit


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value-3.66251051849441300200328663782492136351-9.230275195-5.6-6.3-6.9277766985
Percentage of LongTermDebt0.00.05.30.00.00.09.20.00.00.025.10.00.00.01.14.33.0-0.1-0.1-0.13.47.69.4
Percentage of Assets-0.05.20.91.57.29.81.62.54.95.83.91.02.6-0.10.21.81.3-0.0-0.0-0.01.63.95.0
Percentage of Assets slg:CreditFacility2012 us-gaap:LineOfCredit0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

slg:CreditFacility2017, us-gaap:LineOfCredit


Long
Period End2020-12-312019-12-312018-12-312017-12-31
Value10523449230
Percentage of LongTermDebt5.310.725.11.1
Percentage of Assets0.91.83.90.2
Percentage of Assets slg:CreditFacility2017 us-gaap:LineOfCredit0.00.00.00.0

slg:TermLoan, us-gaap:LineOfCredit


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value15001500150015001500150015001500150015001500150015001500150012001200120012001200930929929
Percentage of LongTermDebt0.00.075.80.00.00.068.70.00.00.076.50.00.00.052.918.518.618.018.318.411.59.28.9
Percentage of Assets13.412.512.812.211.511.311.711.311.011.211.811.110.911.210.77.97.87.67.67.65.34.74.7
Percentage of Assets slg:TermLoan us-gaap:LineOfCredit0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Lessee Operating Lease Liability Payments Due Year Two

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo


Lessee
Period End2021-06-302021-03-312020-12-312020-09-30
Value29292629
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearTwo100.0100.0100.0100.0
Percentage of Assets0.30.20.20.2

Lessee Operating Lease Liability Payments Due Year Three

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree


Lessee
Period End2021-06-302021-03-312020-12-312020-09-30
Value30302327
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearThree100.0100.0100.0100.0
Percentage of Assets0.30.30.20.2

Lessee Operating Lease Liability Payments Due Year Four

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour


Lessee
Period End2021-06-302021-03-312020-12-312020-09-30
Value30302324
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFour100.0100.0100.0100.0
Percentage of Assets0.30.30.20.2

Lessee Operating Lease Liability Payments Due Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive


Lessee
Period End2021-06-302021-03-312020-12-312020-09-30
Value30302424
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFive100.0100.0100.0100.0
Percentage of Assets0.30.30.20.2

Lessee Operating Lease Liability Payments Due After Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive


Lessee
Period End2021-06-302021-03-312020-12-31
Value631631504
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive100.0100.0100.0
Percentage of Assets5.75.24.3

Operating Lease Liability

us-gaap:OperatingLeaseLiability

us-gaap:OperatingLeaseLiability


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value4434553393583613633813843873893.603
Percentage of OperatingLeaseLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets4.03.82.92.92.82.83.02.92.82.90.0

us-gaap:OperatingLeaseLiability us-gaap:ConsolidatedEntities

srt:Subsidiaries


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value4434553393583613633813843873893.603
Percentage of OperatingLeaseLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets4.03.82.92.92.82.83.02.92.82.90.0
Percentage of Assets srt:Subsidiaries4.03.82.92.92.82.83.02.92.82.90.0

us-gaap:OperatingLeaseLiability us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value98398510021015900902897898900901637
Percentage of OperatingLeaseLiability222.0216.4295.3283.3249.3247.9235.1233.7232.4231.317684.4
Percentage of Assets8.88.28.68.26.96.87.06.86.66.75.0
Percentage of Assets us-gaap:CorporateJointVenture5.45.55.30.00.00.05.20.00.00.00.0

Lessee Operating Lease Liability Payments Due

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue


Lessee
Period End2021-06-302021-03-312020-12-312020-09-30
Value797814631756
Percentage of LesseeOperatingLeaseLiabilityPaymentsDue100.0100.0100.0100.0
Percentage of Assets7.16.85.46.1

Lessee Operating Lease Liability Undiscounted Excess Amount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount


Lessee
Period End2021-06-302021-03-312020-12-312020-09-30
Value353359291398
Percentage of LesseeOperatingLeaseLiabilityUndiscountedExcessAmount100.0100.0100.0100.0
Percentage of Assets3.23.02.53.2

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value47894911490950565119526354415692580957975901621461906487622568176935726373247293731872687287723871157148693768446780662565256281623464176419637163216162597560285869509548794388
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets42.940.841.941.039.239.842.642.842.643.346.346.245.148.544.545.145.345.746.246.241.737.136.737.141.241.940.639.740.643.143.643.143.344.144.644.644.744.844.345.846.444.543.241.8

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value4813493549355134520553435517576358795844594762676242653765897184734777037750772277477695771976717524754374597363727271177016676967236905690768606811665264536412626156155397491344814524
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets43.141.042.241.739.840.443.243.343.143.746.646.645.548.947.147.548.048.548.948.944.239.338.939.443.644.243.642.743.546.346.946.446.747.548.048.048.248.347.948.749.549.147.846.80.00.0

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Stockholders
Period End2021-06-302021-03-312020-12-312019-12-31
Value4997583863495437
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest103.8118.3128.698.5
Percentage of Assets44.848.554.242.6
Percentage of Assets us-gaap:CorporateJointVenture27.532.633.631.8

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:RelatedPartyTransactionsByRelatedParty, us-gaap:StatementEquityComponents

us-gaap:CorporateJointVenture, us-gaap:AccumulatedGainLossCashFlowHedgeIncludingNoncontrollingInterest


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302019-12-312018-12-312017-12-312016-12-31
Value-26.63223-10.853-12.732-13.925-7.9824.2995.024.021
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest-0.60.5-0.2-0.2-0.3-0.10.10.10.1
Percentage of Assets-0.20.2-0.1-0.1-0.1-0.10.00.00.0
Percentage of Assets us-gaap:CorporateJointVenture us-gaap:AccumulatedGainLossCashFlowHedgeIncludingNoncontrollingInterest0.00.00.00.00.00.00.00.00.0

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:StatementClassOfStock, us-gaap:StatementEquityComponents

slg:SeriesIPreferredStock, us-gaap:PreferredStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312016-12-312016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312011-12-312010-12-31
Value2212212212212212212212212212212212212212212212212212212212212212212212212212212212212210.00.0
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest4.64.54.54.34.34.24.03.93.83.83.73.53.63.42.92.92.92.92.92.93.03.03.13.13.23.33.33.23.20.00.0
Percentage of Assets2.01.81.91.81.71.71.71.71.61.71.71.61.61.61.41.11.11.11.31.31.31.31.31.41.51.51.51.51.50.00.0
Percentage of Assets slg:SeriesIPreferredStock us-gaap:PreferredStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents

us-gaap:AccumulatedGainLossCashFlowHedgeIncludingNoncontrollingInterest


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302019-12-312018-12-312017-12-312016-12-31
Value-41.483-43.448-57.415-63.698-68.307-22.789.7161212
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest-0.9-0.9-1.2-1.2-1.3-0.40.20.20.2
Percentage of Assets-0.4-0.4-0.5-0.5-0.5-0.20.10.10.1
Percentage of Assets us-gaap:AccumulatedGainLossCashFlowHedgeIncludingNoncontrollingInterest0.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedNetInvestmentGainLossIncludingPortionAttributableToNoncontrollingInterest


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302019-12-312018-12-312017-12-312016-12-31
Value1.2520.7741.0210.23-0.1392.2771.0931.0425.52
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest0.00.00.00.0-0.00.00.00.00.1
Percentage of Assets0.00.00.00.0-0.00.00.00.00.0
Percentage of Assets us-gaap:AccumulatedNetInvestmentGainLossIncludingPortionAttributableToNoncontrollingInterest0.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value-66.863-18.897-67.247-76.2-82.371-80.868-28.485-40.132-28.395-4.005153632281814141622-14.074-16.558-17.222-8.749-15.821-10.906-11.81-6.98-2.896-6.196-14.872-15.211-19.249-18.622-26.117-29.587-29.281-28.413-24.376-28.445-24.462-21.589-13.011-22.659-33.538-54.7474.745
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest-1.4-0.4-1.4-1.5-1.6-1.5-0.5-0.7-0.5-0.10.30.60.50.40.30.20.20.20.3-0.2-0.2-0.2-0.1-0.2-0.1-0.2-0.1-0.0-0.1-0.2-0.2-0.3-0.3-0.4-0.4-0.4-0.4-0.4-0.4-0.4-0.3-0.2-0.4-0.7-1.20.1
Percentage of Assets-0.6-0.2-0.6-0.6-0.6-0.6-0.2-0.3-0.2-0.00.10.30.20.20.10.10.10.10.1-0.1-0.1-0.1-0.0-0.1-0.1-0.1-0.0-0.0-0.0-0.1-0.1-0.1-0.1-0.2-0.2-0.2-0.2-0.2-0.2-0.2-0.2-0.1-0.2-0.30.00.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value3823391338623998402141464286440744514492450846024601477649685294539156515624559654665451543955935570557252895130508550495015475747164697466745894557446942364225410538363660352530793011
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest79.479.378.377.977.377.677.776.575.776.975.873.473.773.175.473.773.473.472.672.570.670.870.572.974.073.970.969.769.970.971.570.370.168.067.666.966.967.265.765.965.668.367.871.868.766.6
Percentage of Assets34.232.533.032.430.831.433.633.232.733.635.434.233.635.735.535.035.235.635.535.431.227.827.428.732.332.630.929.830.432.933.532.632.732.332.432.132.232.531.432.132.533.532.433.60.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AociIncludingPortionAttributableToNoncontrollingInterest


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302019-12-312018-12-312017-12-312016-12-31
Value-66.863-18.897-67.247-76.2-82.371-28.485151822
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest-1.4-0.4-1.4-1.5-1.6-0.50.30.30.3
Percentage of Assets-0.6-0.2-0.6-0.6-0.6-0.20.10.10.1
Percentage of Assets us-gaap:AociIncludingPortionAttributableToNoncontrollingInterest0.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value0.690.7050.7160.7410.7480.7760.8030.8260.8350.8430.8470.8670.8680.9020.9390.9850.9951.0191.0171.0131.0031.0021.0011.0341.0331.0321.010.9960.9930.990.9860.9590.9550.9530.950.940.9360.9250.8920.8920.8780.8440.8170.8090.6040.601
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NoncontrollingInterest


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value2424267785807571694646525149364366411440426429428426431433408394521518492491491488488488487488489490477384392519518524531632
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest0.50.50.51.51.61.51.41.21.20.80.80.80.80.85.55.15.65.75.55.65.55.55.65.65.45.27.07.06.86.97.07.27.37.17.17.17.27.47.46.06.39.39.610.711.914.0
Percentage of Assets0.20.20.20.60.70.60.60.50.50.30.40.40.40.42.62.42.72.82.72.72.42.22.22.22.42.33.13.02.93.23.33.33.43.43.43.43.53.63.52.93.14.54.65.00.00.0
Percentage of Assets us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value93491810151035108110991084122512881210127814761457158311391410143114961578161216551620164317721657169017521813179716881619163616311665170117281741166517041763172112071172949979777
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest19.418.620.620.220.820.619.721.321.920.721.523.623.424.217.319.619.519.420.420.921.421.121.323.122.022.423.524.624.723.723.124.224.324.124.625.225.625.026.427.527.521.521.719.321.917.2
Percentage of Assets8.47.68.78.48.38.38.59.29.59.010.011.010.611.88.19.39.39.410.010.29.48.38.39.19.69.910.310.510.811.010.811.211.311.511.812.112.312.112.613.413.610.610.49.10.00.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:TreasuryStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value-124.049-124.049-124.049-124.049-124.049-124.049-124.049-124.049-124.049-124.049-124.049-124.049-124.049-124.049-124.049-124.049-124.049-124.049-124.049-124.049-10.0-10.0-10.0-335.311-325.207-325.207-320.471-320.222-320.152-320.076-317.356-316.989-316.768-322.858-322.858-319.905-319.866-319.866-308.708-307.535-307.419-306.17-303.222-302.705-302.705-150.719
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest-2.6-2.5-2.5-2.4-2.4-2.3-2.2-2.2-2.1-2.1-2.1-2.0-2.0-1.9-1.9-1.7-1.7-1.6-1.6-1.6-0.1-0.1-0.1-4.4-4.3-4.3-4.3-4.3-4.4-4.5-4.5-4.7-4.7-4.7-4.7-4.7-4.7-4.8-4.8-4.8-4.9-5.5-5.6-6.2-6.8-3.3
Percentage of Assets-1.1-1.0-1.1-1.0-0.9-0.9-1.0-0.9-0.9-0.9-1.0-0.9-0.9-0.9-0.9-0.8-0.8-0.8-0.8-0.8-0.1-0.1-0.1-1.7-1.9-1.9-1.9-1.9-1.9-2.1-2.1-2.2-2.2-2.2-2.2-2.2-2.3-2.3-2.3-2.3-2.4-2.7-2.7-2.90.00.0
Percentage of Assets us-gaap:TreasuryStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Common Stock Value

us-gaap:CommonStockValue

us-gaap:CommonStockValue


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value690000.0705000.0716000.0741000.0748000.0776000.0803000.0826000.0835000.0843000.0847000.0867000.0868000.0902000.0939000.0985000.0995000.01019000.01017000.01013000.01003000.01002000.01001000.01034000.01033000.01032000.01010000.0996000.0993000.0990000.0986000.0959000.0955000.0953000.0950000.0940000.0936000.0925000.0892000.0892000.0878000.0844000.0817000.0809000.0
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Additional Paid In Capital

us-gaap:AdditionalPaidInCapital

us-gaap:AdditionalPaidInCapital


Additional
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value38233913386239984021414642864407445144924508460246014776496852945391565156245596546654515439559355705572528951305085504950154757471646974667458945574469423642254105383636603525
Percentage of AdditionalPaidInCapital100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets34.232.533.032.430.831.433.633.232.733.635.434.233.635.735.535.035.235.635.535.431.227.827.428.732.332.630.929.830.432.933.532.632.732.332.432.132.232.531.432.132.533.532.433.6

Retained Earnings Accumulated Deficit

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:RetainedEarningsAccumulatedDeficit


Retained
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value93491810151035108110991084122512881210127814761457158311391410143114961578161216551620164317721657169017521813179716881619163616311665170117281741166517041763172112071172949
Percentage of RetainedEarningsAccumulatedDeficit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets8.47.68.78.48.38.38.59.29.59.010.011.010.611.88.19.39.39.410.010.29.48.38.39.19.69.910.310.510.811.010.811.211.311.511.812.112.312.112.613.413.610.610.49.1

Accumulated Other Comprehensive Income Loss Net Of Tax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value-66.863-18.897-67.247-76.2-82.371-80.868-28.485-40.132-28.395-4.005153632281814141622-14.074-16.558-17.222-8.749-15.821-10.906-11.81-6.98-2.896-6.196-14.872-15.211-19.249-18.622-26.117-29.587-29.281-28.413-24.376-28.445-24.462-21.589-13.011-22.659-33.538
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets-0.6-0.2-0.6-0.6-0.6-0.6-0.2-0.3-0.2-0.00.10.30.20.20.10.10.10.10.1-0.1-0.1-0.1-0.0-0.1-0.1-0.1-0.0-0.0-0.0-0.1-0.1-0.1-0.1-0.2-0.2-0.2-0.2-0.2-0.2-0.2-0.2-0.1-0.2-0.3

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax us-gaap:ConsolidatedEntities

srt:Subsidiaries


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value-66.863-18.897-67.247-76.2-82.371-80.868-28.485-40.132-28.395-4.0051518
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets-0.6-0.2-0.6-0.6-0.6-0.6-0.2-0.3-0.2-0.00.10.1
Percentage of Assets srt:Subsidiaries-0.6-0.2-0.6-0.6-0.6-0.6-0.2-0.3-0.2-0.00.10.1

Treasury Stock Value

us-gaap:TreasuryStockValue

us-gaap:TreasuryStockValue


Treasury
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value12412412412412412412412412412412412412412412412412412412412410.010.010.0335325325320320320320317316316322322319319319308307307306303302
Percentage of TreasuryStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.11.01.11.00.90.91.00.90.90.91.00.90.90.90.90.80.80.80.80.80.10.10.11.71.91.91.91.91.92.12.12.22.22.22.22.22.32.32.32.32.42.72.72.9

Minority Interest Decrease From Distributions To Noncontrolling Interest Holders

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders


Minority
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value0.0630.11120.1040.4920.2070.0630.2081.1390.4480.2767.357440.140.4694.3961.1571.9617.9054.9561.880.8481121.2741.3932.7661.5862.8143.6573.2734.8796.3243.6234.8827.1170.1059.7621312.21
Percentage of MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders us-gaap:ConsolidatedEntities

srt:Subsidiaries


Minority
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0.0630.11120.1040.4920.2070.0630.2081.1390.4480.276
Percentage of MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.0

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders us-gaap:ConsolidatedEntities, us-gaap:StatementEquityComponents

srt:Subsidiaries, us-gaap:NoncontrollingInterest


Minority
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0.0630.11120.1040.4920.2070.0630.2081.1390.4480.276
Percentage of MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets srt:Subsidiaries us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.0

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Minority
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value0.0630.11120.1040.4920.2070.0630.2081.1390.4480.2767.357440.140.4694.3961.1571.9617.9054.9561.880.8481121.2741.3932.7661.5862.8143.6573.2734.8796.3243.6234.8827.1170.1059.7621312.21
Percentage of MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value8418226103182427781155621237115194131102197116125135259114203891429011310018888759611010287681415675609779671018566
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating23258.84782.050064.817868.628129.58422.013732.613407.66554.410743.613978.817569.743582.229919.641826.028904.250270.522295.415356.3205172.724788.513189.625595.611538.719628.113950.817766.912870.134133.016569.213150.917223.123609.122632.520802.617622.035188.013861.216026.411907.618037.016455.58418.221212.317057.90.0

us-gaap:NetCashProvidedByUsedInOperatingActivities us-gaap:ConsolidatedEntities

srt:Subsidiaries


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value8418226103182427781155621237115194
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating23258.84782.050064.817868.628129.58422.013732.613407.66554.410743.613978.817569.743582.229919.6
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value62120681-28.796533-129.418355225-174.561-291.843181232-187.93845682162-293.57729-282.6032781787338-279.485-1728.493-488.2323028-507.222-246.24-71.801-385.97-195.943127-174.49-341.217-271.129-263.855-294.192-238.078-436.786-95.73230-156.175-71.909307-60.243
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating170697.85187.9150753.8-4964.882289.7-25935.563350.137089.5-7353.0-50317.820454.357184.2-54005.2144304.426092.145711.2-74701.55720.5-34463.8421857.6170926.439174.2-35155.3-222743.9-67249.335321.64462.8-64862.1-44608.7-13496.4-67008.7-34803.427227.2-38518.8-80857.1-70240.7-65799.3-71754.1-50762.9-85476.7-17794.16391.5-19620.0-15043.760940.90.0

us-gaap:NetCashProvidedByUsedInInvestingActivities us-gaap:ConsolidatedEntities

srt:Subsidiaries


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value62120681-28.796533-129.418355225-174.561-291.843181232-187.938456
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating170697.85187.9150753.8-4964.882289.7-25935.563350.137089.5-7353.0-50317.820454.357184.2-54005.2144304.4
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-791.108-9.971-839.354-871.676-235.255466-407.548-331.625-35.605246-284.901-424.88937-422.309-327.543-295.107-101.0564230-284.17-2087.157-392.141871667230-271.895-113.714351-81.233224307109-260.066102281108245232-93.399380154-209.629151-98.26-221.191-182.5
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating-217337.4-2563.2-185697.8-150289.0-36304.893584.0-72646.7-54543.6-1499.842435.9-32119.6-104652.510915.8-133642.1-103981.9-82895.2-25714.08182.13686.3-430560.6-199537.0-45334.210948.3214873.331798.3-41701.7-17851.545012.1-14716.142128.453440.119379.4-55333.222535.366599.828153.461318.056788.8-19914.574405.928794.2-43222.518994.1-20556.5-43887.10.0

us-gaap:NetCashProvidedByUsedInFinancingActivities us-gaap:ConsolidatedEntities

srt:Subsidiaries


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-791.108-9.971-839.354-871.676-235.255466-407.548-331.625-35.605246-284.901-424.88937-422.309
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating-217337.4-2563.2-185697.8-150289.0-36304.893584.0-72646.7-54543.6-1499.842435.9-32119.6-104652.510915.8-133642.1
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-85.1062868-796.83448037924-24.603-54.5641620-121.3881.715128-99.226-31.672-158.326169
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating-23380.87406.715120.8-137385.274114.476070.54436.0-4046.5-2298.42861.72313.5-29898.5492.840582.0-31500.3-8896.6-40286.532491.9

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect us-gaap:ConsolidatedEntities

srt:Subsidiaries


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-85.1062868-796.83448037924-24.603-54.5641620-121.3881.715128
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating-23380.87406.715120.8-137385.274114.476070.54436.0-4046.5-2298.42861.72313.5-29898.5492.840582.0
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Amortization Of Financing Costs

us-gaap:AmortizationOfFinancingCosts

us-gaap:AmortizationOfFinancingCosts


Amortization
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3.3863.7743.4823.1512.6612.53.0873.1122.7122.7422.6952.633.5463.5374.2974.0083.4324.7614.3844.8157.4337.9327.6217.165.9526.6156.646.6795.53.8683.6614.3314.244.4637.8244.4933.5533.584.632.9922.693.8063.482.5811.5712.295
Percentage of AmortizationOfFinancingCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AmortizationOfFinancingCosts us-gaap:ConsolidatedEntities

srt:Subsidiaries


Amortization
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value3.3863.7743.4823.1512.6612.53.0873.1122.7122.7422.6952.633.5463.537
Percentage of AmortizationOfFinancingCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AmortizationOfFinancingCosts us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Amortization
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value7.2046.3845.235.5754.8084.8144.9024.4364.7825.2164.7224.4467.355.1165.0324.037.4586.505
Percentage of AmortizationOfFinancingCosts212.8169.2150.2176.9180.7192.6158.8142.5176.3190.2175.2169.0207.3144.6117.1100.5217.3136.6

Depreciation Depletion And Amortization

us-gaap:DepreciationDepletionAndAmortization

us-gaap:DepreciationDepletionAndAmortization


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value606660959870677372717473717288951369810811743218711415320511410410110093929187851018781807976726350605555
Percentage of DepreciationDepletionAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DepreciationDepletionAndAmortization us-gaap:ConsolidatedEntities

srt:Subsidiaries


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value6066609598706773727174737172
Percentage of DepreciationDepletionAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Increase Decrease In Accounts Receivable

us-gaap:IncreaseDecreaseInAccountsReceivable

us-gaap:IncreaseDecreaseInAccountsReceivable


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-1.6454.138-25.995-14.2561244-2.5966.455-3.654.759-3.782-3.583-1.451.8473.3993.765-0.175-1.272-2.0662.1063.009-7.829-2.0931.67213-7.096-9.314136.009-11.8994.5527.9142.513-7.4092.4983.4945.02-0.0141.592.2891.866-1.025-3.6237.245-3.48-0.413
Percentage of IncreaseDecreaseInAccountsReceivable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInAccountsReceivable us-gaap:ConsolidatedEntities

srt:Subsidiaries


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-1.6454.138-25.995-14.2561244-2.5966.455-3.654.759-3.782-3.583-1.451.847
Percentage of IncreaseDecreaseInAccountsReceivable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value8418226103182427781155621237115194131102197116125135259114203891429011310018888759611010287681415675609779671018566
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating23258.84782.050064.817868.628129.58422.013732.613407.66554.410743.613978.817569.743582.229919.641826.028904.250270.522295.415356.3205172.724788.513189.625595.611538.719628.113950.817766.912870.134133.016569.213150.917223.123609.122632.520802.617622.035188.013861.216026.411907.618037.016455.58418.221212.317057.90.0

us-gaap:NetCashProvidedByUsedInOperatingActivities us-gaap:ConsolidatedEntities

srt:Subsidiaries


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value8418226103182427781155621237115194
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating23258.84782.050064.817868.628129.58422.013732.613407.66554.410743.613978.817569.743582.229919.6
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value109-3.7261741760118213616447-57.4829110710531421115473713726105167-35.368476068239149404027262725110331014534881411914422
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating29964.0-957.838658.83034.09287.223755.33773.46068.36943.68194.8-6480.522647.030831.333387.310069.511968.33043.02896.25823.557560.613116.13116.613212.721571.6-4871.67210.99501.68750.143347.628163.27093.27240.35837.25809.36484.16646.927577.18097.12207.02861.899257.118233.41853.524904.828687.10.0

us-gaap:NetIncomeLoss us-gaap:ConsolidatedEntities

srt:Subsidiaries


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value115-4.2021841863124223817349-60.9219611211033441215
Percentage of NetIncomeLoss105.8112.8105.7104.6105.1105.2104.7104.7105.0104.8106.0105.2105.2105.0104.1104.3103.5103.2
Percentage of InterestIncomeOperating31689.8-1080.240858.63172.29761.024998.23950.66351.07293.68587.6-6868.223828.632436.535055.710478.412477.23149.62987.5
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Profit Loss

us-gaap:ProfitLoss

us-gaap:ProfitLoss


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value117-3.8552002066127244017352-58.32991151133845160.924534314932114176-29.179556573250156444531302728118351716549931712415026
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating32179.7-991.044323.03565.010281.925473.74323.56697.77318.59098.1-6575.024496.133304.336019.912169.812863.84075.1177.46581.765671.214253.83757.614370.922777.4-4019.18533.110255.19411.045350.029438.37701.78052.66648.56696.96506.47417.129540.48574.93743.13226.6102079.419359.62256.226059.829860.90.0

us-gaap:ProfitLoss us-gaap:ConsolidatedEntities

srt:Subsidiaries


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value117-3.8552002066127244017352-58.3299115113
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating32179.7-991.044323.03565.010281.925473.74323.56697.77318.59098.1-6575.024496.133304.336019.9
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ProfitLoss us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Profit
Period End2021-06-302021-03-312020-06-302020-03-31
Value-17.495-4.94-5.056-18.525
Percentage of ProfitLoss-14.9128.1-7.6-14.6
Percentage of InterestIncomeOperating-4806.3-1269.9-780.2-3712.4
Percentage of InterestIncomeOperating us-gaap:CorporateJointVenture0.00.00.00.0

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value62120681-28.796533-129.418355225-174.561-291.843181232-187.93845682162-293.57729-282.6032781787338-279.485-1728.493-488.2323028-507.222-246.24-71.801-385.97-195.943127-174.49-341.217-271.129-263.855-294.192-238.078-436.786-95.73230-156.175-71.909307-60.243
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating170697.85187.9150753.8-4964.882289.7-25935.563350.137089.5-7353.0-50317.820454.357184.2-54005.2144304.426092.145711.2-74701.55720.5-34463.8421857.6170926.439174.2-35155.3-222743.9-67249.335321.64462.8-64862.1-44608.7-13496.4-67008.7-34803.427227.2-38518.8-80857.1-70240.7-65799.3-71754.1-50762.9-85476.7-17794.16391.5-19620.0-15043.760940.90.0

us-gaap:NetCashProvidedByUsedInInvestingActivities us-gaap:ConsolidatedEntities

srt:Subsidiaries


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value62120681-28.796533-129.418355225-174.561-291.843181232-187.938456
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating170697.85187.9150753.8-4964.882289.7-25935.563350.137089.5-7353.0-50317.820454.357184.2-54005.2144304.4
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Payments To Acquire Real Estate

us-gaap:PaymentsToAcquireRealEstate us-gaap:BusinessAcquisition, us-gaap:SubsequentEventType

us-gaap:PaymentsToAcquireRealEstate

slg:FifthAvenue461, us-gaap:SubsequentEvent


Payments
Period End2021-04-30
Value28
Percentage of PaymentsToAcquireRealEstate100.0

Payments To Acquire Investments

us-gaap:PaymentsToAcquireInvestments

us-gaap:PaymentsToAcquireInvestments


Payments
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value8842223329343048374229814524024223271101172957421217419616410615016111582195
Percentage of PaymentsToAcquireInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsToAcquireInvestments us-gaap:ConsolidatedEntities

srt:Subsidiaries


Payments
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value8842223329343048374229
Percentage of PaymentsToAcquireInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-791.108-9.971-839.354-871.676-235.255466-407.548-331.625-35.605246-284.901-424.88937-422.309-327.543-295.107-101.0564230-284.17-2087.157-392.141871667230-271.895-113.714351-81.233224307109-260.066102281108245232-93.399380154-209.629151-98.26-221.191-182.5
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating-217337.4-2563.2-185697.8-150289.0-36304.893584.0-72646.7-54543.6-1499.842435.9-32119.6-104652.510915.8-133642.1-103981.9-82895.2-25714.08182.13686.3-430560.6-199537.0-45334.210948.3214873.331798.3-41701.7-17851.545012.1-14716.142128.453440.119379.4-55333.222535.366599.828153.461318.056788.8-19914.574405.928794.2-43222.518994.1-20556.5-43887.10.0

us-gaap:NetCashProvidedByUsedInFinancingActivities us-gaap:ConsolidatedEntities

srt:Subsidiaries


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-791.108-9.971-839.354-871.676-235.255466-407.548-331.625-35.605246-284.901-424.88937-422.309
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestIncomeOperating-217337.4-2563.2-185697.8-150289.0-36304.893584.0-72646.7-54543.6-1499.842435.9-32119.6-104652.510915.8-133642.1
Percentage of InterestIncomeOperating srt:Subsidiaries0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Payments Of Dividends

us-gaap:PaymentsOfDividends

us-gaap:PaymentsOfDividends


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value68696970737975767777767678818183848479787878656464625251515135334038293230281616151515151512
Percentage of PaymentsOfDividends100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsOfDividends us-gaap:ConsolidatedEntities

srt:Subsidiaries


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value7273737477807979808179808285
Percentage of PaymentsOfDividends105.8105.9105.4105.3105.2101.6104.9104.8104.8104.7104.6104.9104.9104.7

Payments For Repurchase Of Common Stock

us-gaap:PaymentsForRepurchaseOfCommonStock

us-gaap:PaymentsForRepurchaseOfCommonStock


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312012-12-312012-09-302011-12-312011-09-30
Value948414629132219209657534219353423824561382110.1020.00.00.00.02.9530.0391.1730.116
Percentage of PaymentsForRepurchaseOfCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0100.0100.0100.0100.0

us-gaap:PaymentsForRepurchaseOfCommonStock us-gaap:ConsolidatedEntities

srt:Subsidiaries


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value94841462913221920965753421935342382
Percentage of PaymentsForRepurchaseOfCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice us-gaap:AwardType

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice

us-gaap:EmployeeStockOption


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302011-12-312010-12-312009-12-31
Value102.77102.83102.62101.88102.17102.32102.36103.24103.31103.5135.54101.98101.43101.37101.4899.599.4599.1898.4497.1896.3295.5995.5290.389.6689.1987.9885.6585.5384.8983.2479.2578.176.8175.0573.563.3758.8556.74
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonthsIntoEquityInNetIncome

slg:CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonthsIntoEquityInNetIncome


Cash
Period End2021-06-302021-03-31
Value3600000.02200000.0
Percentage of CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonthsIntoEquityInNetIncome100.0100.0

slg:CommonStockDividendsPerShareStockPaid slg:DividendType, us-gaap:StatementEquityComponents

slg:CommonStockDividendsPerShareStockPaid

slg:CashDividend, us-gaap:CommonStock


Common
Period End2021-01-15
Value0.0279
Percentage of CommonStockDividendsPerShareStockPaid100.0

slg:StockDividend, us-gaap:CommonStock


Common
Period End2021-01-15
Value0.0343
Percentage of CommonStockDividendsPerShareStockPaid122.9

slg:ConsolidationOfJointVentureInterest

slg:ConsolidationOfJointVentureInterest


Consolidation
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value0.1340.1714.2194.3723.8142.404500.1613.0721.6710.1573.0730.1931.062310.340.5850.50.9340.743254.3830.4170.2543.116.7130.3820.46818870.0
Percentage of ConsolidationOfJointVentureInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

slg:ConsolidationOfJointVentureInterest us-gaap:ConsolidatedEntities

srt:Subsidiaries


Consolidation
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0.1340.1714.2194.3723.8142.404500.1613.0721.6710.157
Percentage of ConsolidationOfJointVentureInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:ConsolidationOfJointVentureInterest us-gaap:ConsolidatedEntities, us-gaap:StatementEquityComponents

srt:Subsidiaries, us-gaap:NoncontrollingInterest


Consolidation
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0.1340.1714.2194.3723.8142.404500.1613.0721.6710.157
Percentage of ConsolidationOfJointVentureInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:ConsolidationOfJointVentureInterest us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Consolidation
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value0.1340.1714.2194.3723.8142.404500.1613.0721.6710.1573.0730.1931.062310.340.5850.50.9340.743254.3830.4170.2543.116.7130.3820.46818870.0
Percentage of ConsolidationOfJointVentureInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

slg:ConsolidationOfRealEstateInvestment

slg:ConsolidationOfRealEstateInvestment


Consolidation
Period End2021-06-302021-03-31
Value0.0119
Percentage of ConsolidationOfRealEstateInvestment0.0100.0

slg:ConsolidationOfRealEstateInvestment us-gaap:ConsolidatedEntities

srt:Subsidiaries


Consolidation
Period End2021-06-302021-03-31
Value0.0119
Percentage of ConsolidationOfRealEstateInvestment0.0100.0

slg:DebtAndEquitySecuritiesCreditLossExpenseReversal

slg:DebtAndEquitySecuritiesCreditLossExpenseReversal


Debt
Period End2020-09-302020-06-302020-03-31
Value8.9573.3818.403
Percentage of DebtAndEquitySecuritiesCreditLossExpenseReversal100.0100.0100.0

slg:DebtAndPreferredEquityReserves

slg:DebtAndPreferredEquityReserves


Debt
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-06-302019-03-31
Value-4816000.010000000.04376000.0004638000.000
Percentage of DebtAndPreferredEquityReserves100.0100.0100.00.00.0100.00.00.0

slg:DebtAndPreferredEquityReserves us-gaap:ConsolidatedEntities

srt:Subsidiaries


Debt
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-06-302019-03-31
Value-4816000.010000000.04376000.0004638000.000
Percentage of DebtAndPreferredEquityReserves100.0100.0100.00.00.0100.00.00.0

slg:DeferredCompensationPlanAndStockAwardNet

slg:DeferredCompensationPlanAndStockAwardNet


Deferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value7.5916.7287.5437.9915.502-5.948-5.698-4.835-4.634-4.988-3.10231-6.5110.02-1.9630.0980.0640.07-2.220.1140.0020.332-3.43-0.1510.0270.035-1.425-0.268-2.8620.0480.071-10.685-1.095-0.04-1.178-2.474
Percentage of DeferredCompensationPlanAndStockAwardNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:DeferredCompensationPlanAndStockAwardNet us-gaap:ConsolidatedEntities

srt:Subsidiaries


Deferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value7.5916.7287.5437.9915.502-5.948-5.698-4.835-4.634-4.988-3.102
Percentage of DeferredCompensationPlanAndStockAwardNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:DeferredCompensationPlanAndStockAwardNet us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents

srt:Subsidiaries, us-gaap:GeneralPartner, us-gaap:CommonStock


Deferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value7.5916.7287.5437.9915.502-5.948-5.698-4.835-4.634-4.988-3.102
Percentage of DeferredCompensationPlanAndStockAwardNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:DeferredCompensationPlanAndStockAwardNet us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Deferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value7.5916.7267.5437.995.503-5.948-5.698-4.835-4.634-4.988-3.10231-6.5110.02-1.9630.0970.0640.07-2.22-1.5010.1060.3321.3060.0980.0970.1111.2950.0970.090.0880.0710.470.0780.0760.0710.471
Percentage of DeferredCompensationPlanAndStockAwardNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.099.0100.0100.0100.0-1316.75300.0100.0-38.1-64.9359.3317.1-90.9-36.2-3.1183.3100.0-4.4-7.1-190.0-6.0-19.0

us-gaap:CommonStock


Deferred
Period End2021-03-312020-06-302020-03-312015-12-312014-09-302014-06-302014-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value0.0020.001-0.0010.0020.00.00.00.001-0.0010.00.0030.00.00.00.003
Percentage of DeferredCompensationPlanAndStockAwardNet0.00.0-0.01.80.00.0-0.0-0.0-2.10.0-0.0-0.0-0.0-0.0-0.1

slg:DeferredCompensationPlanAndStockAwardShares us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents

slg:DeferredCompensationPlanAndStockAwardShares

srt:Subsidiaries, us-gaap:GeneralPartner, us-gaap:CommonStock


Deferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value-1000.0113000.03000.00-33000.0-21000.0-3000.020000.0-13000.01000.019000.0
Percentage of DeferredCompensationPlanAndStockAwardShares100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0

slg:DeferredCompensationPlanAndStockAwardShares us-gaap:StatementEquityComponents

us-gaap:CommonStock


Deferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value-1000.0113000.03000.00-33000.0-21000.0-3000.020000.0-13000.01000.019000.081000.0-2000.0-2000.010000.084000.08000.0-21000.025000.0140000.0
Percentage of DeferredCompensationPlanAndStockAwardShares100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.00.00.0

slg:DeferredLoanCostsAndCapitalizedLeaseObligation

slg:DeferredLoanCostsAndCapitalizedLeaseObligation


Deferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.1820.28818150.5626.444113.3676.7211.1070.4290.4720.8097.7121.234301.9047.4033119-0.0474.4056.7466.397403.4267.1210.429-0.1858.677152.363255.56938-22.4815.69313102.8732.02731
Percentage of DeferredLoanCostsAndCapitalizedLeaseObligation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:DeferredLoanCostsAndCapitalizedLeaseObligation us-gaap:ConsolidatedEntities

srt:Subsidiaries


Deferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0.1820.28818150.5626.444113.3676.7211.1070.429
Percentage of DeferredLoanCostsAndCapitalizedLeaseObligation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:DepreciableRealEstateReservesAndImpairment

slg:DepreciableRealEstateReservesAndImpairment


Depreciable
Period End2021-06-302021-03-312020-09-302019-09-30
Value-2545000.08241000.06627000.07047000.0
Percentage of DepreciableRealEstateReservesAndImpairment100.0100.0100.0100.0

slg:DepreciableRealEstateReservesAndImpairment us-gaap:ConsolidatedEntities

srt:Subsidiaries


Depreciable
Period End2021-06-302021-03-312020-09-302019-09-30
Value-2545000.08241000.06627000.07047000.0
Percentage of DepreciableRealEstateReservesAndImpairment100.0100.0100.0100.0

slg:DistributedEarningsDiluted

slg:DistributedEarningsDiluted


Distributed
Period End2021-06-302020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-30
Value-246000.0250000.00448000.00164000.00125000.055000.042000.0109000.0
Percentage of DistributedEarningsDiluted100.0100.00.0100.00.0100.00.0100.0100.0100.0100.0

slg:DistributedEarningsDiluted us-gaap:ConsolidatedEntities

srt:Subsidiaries


Distributed
Period End2021-06-302020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value246000.0-250000.00448000.00164000.0033000.055000.042000.0
Percentage of DistributedEarningsDiluted-100.0-100.00.0100.00.0100.00.026.4100.0100.0

slg:DistributionToNoncontrollingInterestOperatingPartnership

slg:DistributionToNoncontrollingInterestOperatingPartnership


Distribution
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3.9624.1483.7953.7473.8261.2843.7363.643.713.6433.5313.7573.8713.8413.6273.5273.5753.5373.4263.2363.1282.8812.6932.3242.3442.3492.3671.8842.0981.51.4510.920.9220.8530.9110.8240.7990.7620.1550.190.1540.2280.1240.1250.1210.141
Percentage of DistributionToNoncontrollingInterestOperatingPartnership100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:DistributionsPreferredUnits us-gaap:ConsolidatedEntities

slg:DistributionsPreferredUnits

srt:Subsidiaries


Distributions
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value3.7373.7383.7383.7373.7382.0913.7383.7373.7382.6012.713.023.0475.3281.3763.637-14.641
Percentage of DistributionsPreferredUnits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:DistributionsPreferredUnits us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents

srt:Subsidiaries, us-gaap:GeneralPartner, us-gaap:CommonStock


Distributions
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value3.7373.7383.7383.7373.7383.7383.7373.7383.7383.7373.738
Percentage of DistributionsPreferredUnits100.0100.0100.0100.0100.0100.0100.0100.0137.9123.7122.7

slg:DistributionsToNoncontrollingInterestsOtherPartnerships

slg:DistributionsToNoncontrollingInterestsOtherPartnerships


Distributions
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.0630.1172120.1040.4920.00.2070.0630.2086.5011.1390.4480.2767.357440.140.4694.3961.1571.9617.9056.1891.880.8481101.2741.3932.7661.5862.8143.6573.2734.8796.3243.6234.8827.1170.1049.7621312.212.5374.1383.5073.307
Percentage of DistributionsToNoncontrollingInterestsOtherPartnerships100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:DistributionsToNoncontrollingInterestsOtherPartnerships us-gaap:ConsolidatedEntities

srt:Subsidiaries


Distributions
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.0630.1172120.1040.4920.00.2070.0630.2086.5011.1390.4480.276
Percentage of DistributionsToNoncontrollingInterestsOtherPartnerships100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0

slg:EquityMethodInvestmentsOwnershipPercentageAcquired us-gaap:StatementGeographical

slg:EquityMethodInvestmentsOwnershipPercentageAcquired

slg:WorldwidePlaza


Equity
Period End2021-05-31
Value1.2
Percentage of EquityMethodInvestmentsOwnershipPercentageAcquired100.0

slg:EquityMethodInvestmentsOwnershipPercentageIncreaseDecrease us-gaap:StatementGeographical

slg:EquityMethodInvestmentsOwnershipPercentageIncreaseDecrease

slg:WorldwidePlaza


Equity
Period End2021-05-31
Value0.6
Percentage of EquityMethodInvestmentsOwnershipPercentageIncreaseDecrease100.0

slg:ExtinguishmentOfDebtInConnectionWithPropertyDispositions

slg:ExtinguishmentOfDebtInConnectionWithPropertyDispositions


Extinguishment
Period End2021-06-302021-03-31
Value0.053
Percentage of ExtinguishmentOfDebtInConnectionWithPropertyDispositions0.0100.0

slg:ExtinguishmentOfDebtInConnectionWithPropertyDispositions us-gaap:ConsolidatedEntities

srt:Subsidiaries


Extinguishment
Period End2021-06-302021-03-31
Value0.053
Percentage of ExtinguishmentOfDebtInConnectionWithPropertyDispositions0.0100.0

slg:FinanceLeaseCost

slg:FinanceLeaseCost


Finance
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value1674000.01672000.02367000.01914000.01411000.02000000.01123000.01117000.01113000.01100000.0
Percentage of FinanceLeaseCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:FinanceLeaseInterestExpenseBeforeCapitalizedInterest

slg:FinanceLeaseInterestExpenseBeforeCapitalizedInterest


Finance
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value1494000.01492000.02081000.02198000.02149000.01663000.0818000.0813000.0808000.0
Percentage of FinanceLeaseInterestExpenseBeforeCapitalizedInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:FinanceLeaseInterestExpenseCapitalized

slg:FinanceLeaseInterestExpenseCapitalized


Finance
Period End2020-12-312020-09-302020-06-302020-03-312019-06-30
Value0588000.01043000.0747000.00
Percentage of FinanceLeaseInterestExpenseCapitalized0.0100.0100.0100.00.0

slg:FinancingReceivableAllowanceForCreditLossesWriteOffsAndReclassifications

slg:FinancingReceivableAllowanceForCreditLossesWriteOffsAndReclassifications


Financing
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312014-12-312014-09-302014-06-302014-03-312013-12-312012-12-31
Value5.056260.00.00.00.04.02.0-2.00.01.03.00.0
Percentage of FinancingReceivableAllowanceForCreditLossesWriteOffsAndReclassifications100.0100.00.00.00.00.0100.0100.0100.00.0100.0100.00.0

slg:IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment

slg:IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value117-3.8552002066127244017352-58.32994747554435512642-70.4638.8155620-29.948424227585136303729-6.5833108218.248112678
Percentage of IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, slg:RealEstateSegment


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-30
Value100-20.0271921040111-9.6676.13314021-95.356621314174.873-18.56111-13.355-33.613-112.337-39.03118-22.486-65.6776.7599.03-10.54223
Percentage of IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment85.6519.596.348.860.187.5-39.915.181.140.9163.562.927.929.631.010.9-51.822.8-51.0-78.7159.4-442.831.7-107.1219.316.021.4-38.339.6

us-gaap:OperatingSegments, slg:StructuredFinanceSegment


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-30
Value16167.3751026153334323137363433373954393976414738433535333833
Percentage of IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment14.4-419.53.751.239.912.5139.984.918.959.1-63.537.172.170.469.089.1151.877.2151.0178.7-59.4542.868.3207.1-119.384.078.6138.358.3

slg:IncreaseDecreaseInAccruedLiabilitiesAndOther

slg:IncreaseDecreaseInAccruedLiabilitiesAndOther


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-21.952-38.64883.93853-13.877-44.3341318-12.915-16.305-2.1523.97718-13.213125.667-16.327-7.5395.546-13.005-20.632.515233.243-20.23-25.2414.47214-1.821-25.108210.9240.869-1.921.75.4914.118-1.988180.51-5.833-13.977-6.4334.41212
Percentage of IncreaseDecreaseInAccruedLiabilitiesAndOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:IncreaseDecreaseInAccruedLiabilitiesAndOther us-gaap:ConsolidatedEntities

srt:Subsidiaries


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-21.952-38.64883.93853-13.877-44.3341318-12.915-16.305-2.1523.97718
Percentage of IncreaseDecreaseInAccruedLiabilitiesAndOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:IncreaseDecreaseInOperatingLeaseLiability

slg:IncreaseDecreaseInOperatingLeaseLiability


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-12072000.0-19160000.0-2839000.0-2802000.0-2769000.0-2959000.0-3138000.0-2941000.0-2255000.0-2866000.0
Percentage of IncreaseDecreaseInOperatingLeaseLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:IncreaseDecreaseInOperatingLeaseLiability us-gaap:ConsolidatedEntities

srt:Subsidiaries


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-12072000.0-19160000.0-2839000.0-2802000.0-2769000.0-2959000.0-3138000.0-2941000.0-2255000.0-2866000.0
Percentage of IncreaseDecreaseInOperatingLeaseLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:IncrementalCommonSharesAttributableToRedemptionOfUnitsToCommonShares

slg:IncrementalCommonSharesAttributableToRedemptionOfUnitsToCommonShares


Incremental
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value4093000.04148000.0-27000.04029000.04120000.04220000.0-8000.04258000.04260000.04333000.0-115000.04643000.04706000.04683000.0-14000.04543000.04562000.04607000.051000.04497000.04342000.03974000.0-25000.03901000.003964000.091000.03585000.03515000.03079000.02652000.02687000.019000.03320000.03193000.03049000.0109000.01912000.01912000.01805000.0-24000.01210000.01325000.0
Percentage of IncrementalCommonSharesAttributableToRedemptionOfUnitsToCommonShares100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:IncrementalCommonUnitsAttributableToDilutiveEffectOfNonvestedSharesWithForfeitableDividends us-gaap:ConsolidatedEntities

slg:IncrementalCommonUnitsAttributableToDilutiveEffectOfNonvestedSharesWithForfeitableDividends

srt:Subsidiaries


Incremental
Period End2021-06-302021-03-31
Value-160000.0317000.0
Percentage of IncrementalCommonUnitsAttributableToDilutiveEffectOfNonvestedSharesWithForfeitableDividends100.0100.0

slg:IncrementalCommonUnitsAttributabletoSharebasedPaymentArrangements us-gaap:ConsolidatedEntities

slg:IncrementalCommonUnitsAttributabletoSharebasedPaymentArrangements

srt:Subsidiaries


Incremental
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value654000.0595000.00442000.0409000.0483000.0383000.0164000.0167000.0164000.04000.0219000.0201000.053000.0
Percentage of IncrementalCommonUnitsAttributabletoSharebasedPaymentArrangements100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:InterestExpenseNet

slg:InterestExpenseNet


Interest
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value182323303748475055534765646564728994888475758082788082828381828582807675686563565656
Percentage of InterestExpenseNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:InterestExpenseNet us-gaap:ConsolidatedEntities

srt:Subsidiaries


Interest
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value1823233037484750555347
Percentage of InterestExpenseNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:InterestExpenseNet us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Interest
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value797986929396889189615955
Percentage of InterestExpenseNet338.7264.8230.2192.5198.7191.2160.1170.9187.393.092.184.3

slg:IssuanceOfSpecialDividendStockDividend

slg:IssuanceOfSpecialDividendStockDividend


Issuance
Period End2021-06-302021-03-31
Value0.0123
Percentage of IssuanceOfSpecialDividendStockDividend0.0100.0

slg:IssuanceOfSpecialDividendStockDividend us-gaap:ConsolidatedEntities

srt:Subsidiaries


Issuance
Period End2021-06-302021-03-31
Value0.0123
Percentage of IssuanceOfSpecialDividendStockDividend0.0100.0

slg:MinorityInterestIncreaseDecreaseFromFairValueAdjustment us-gaap:ConsolidatedEntities

slg:MinorityInterestIncreaseDecreaseFromFairValueAdjustment

srt:PartnershipInterest


Minority
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value5.866262.655-4.1097.385-38.529
Percentage of MinorityInterestIncreaseDecreaseFromFairValueAdjustment100.0100.0100.0100.0100.0100.0

slg:NetIncomeLossAllocatedToCommonUnitholders us-gaap:ConsolidatedEntities

slg:NetIncomeLossAllocatedToCommonUnitholders

srt:Subsidiaries


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value111-7.941801459121183416946-64.6589310910729408.64111
Percentage of NetIncomeLossAllocatedToCommonUnitholders100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:NetIncomeLossAvailableToCommonStockholdersAfterDistributedAndUndistributedEarningsAllocationBasic

slg:NetIncomeLossAvailableToCommonStockholdersAfterDistributedAndUndistributedEarningsAllocationBasic


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value104-7.8351701356114163316043-61.262881031012738
Percentage of NetIncomeLossAvailableToCommonStockholdersAfterDistributedAndUndistributedEarningsAllocationBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:NetIncomeLossAvailableToCommonStockholdersAfterDistributedAndUndistributedEarningsAllocationBasic us-gaap:ConsolidatedEntities

srt:Subsidiaries


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value110-8.3111801459120173416945-64.70292108106
Percentage of NetIncomeLossAvailableToCommonStockholdersAfterDistributedAndUndistributedEarningsAllocationBasic106.0106.1105.8105.9105.5105.4106.2105.2105.2105.2105.6105.4105.4105.2

slg:NonCashLeaseExpense

slg:NonCashLeaseExpense


Non
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value4.1633.3752.2493.1883.1573.393.4893.4573.4173.381
Percentage of NonCashLeaseExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:NonCashLeaseExpense us-gaap:ConsolidatedEntities

srt:Subsidiaries


Non
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value4.1633.3752.2493.1883.1573.393.4893.4573.4173.381
Percentage of NonCashLeaseExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:NoncontrollingInterestAccruedDividendsOnPreferredUnits us-gaap:ConsolidatedEntities, us-gaap:StatementClassOfStock

slg:NoncontrollingInterestAccruedDividendsOnPreferredUnits

srt:Subsidiaries, us-gaap:PreferredStock


Noncontrolling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value1673000.01696000.00-329000.0-163000.02126000.0
Percentage of NoncontrollingInterestAccruedDividendsOnPreferredUnits100.0100.00.0100.0100.0100.0

slg:NoncontrollingInterestDecreaseFromDistributionOnPreferredUnits us-gaap:ConsolidatedEntities, us-gaap:StatementClassOfStock

slg:NoncontrollingInterestDecreaseFromDistributionOnPreferredUnits

srt:Subsidiaries, us-gaap:PreferredStock


Noncontrolling
Period End2021-06-302021-03-31
Value1673000.01731000.0
Percentage of NoncontrollingInterestDecreaseFromDistributionOnPreferredUnits100.0100.0

slg:NoncontrollingInterestDecreasefromDistributionstoOtherNoncontrollingInterestHolders us-gaap:ConsolidatedEntities

slg:NoncontrollingInterestDecreasefromDistributionstoOtherNoncontrollingInterestHolders

srt:PartnershipInterest


Noncontrolling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value3.9624.1483.7953.7473.8261.284
Percentage of NoncontrollingInterestDecreasefromDistributionstoOtherNoncontrollingInterestHolders100.0100.0100.0100.0100.0100.0

slg:OperatingLeaseCostBeforeCapitalizedOperatingLeaseCosts

slg:OperatingLeaseCostBeforeCapitalizedOperatingLeaseCosts


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value7.5687.5677.6837.7518.6228.1138.3178.3158.305
Percentage of OperatingLeaseCostBeforeCapitalizedOperatingLeaseCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:OperatingLeaseCostCapitalized

slg:OperatingLeaseCostCapitalized


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value861000.0828000.0812000.0778000.0791000.0746000.020000.020000.07000.0
Percentage of OperatingLeaseCostCapitalized100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:OperatingLeaseLeaseIncomeFixedAndVariableLeasePayments

slg:OperatingLeaseLeaseIncomeFixedAndVariableLeasePayments


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value186189189193194221249246243238246249
Percentage of OperatingLeaseLeaseIncomeFixedAndVariableLeasePayments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:OperatingPartnershipNoncontrollingInterestFairValueAdjustment

slg:OperatingPartnershipNoncontrollingInterestFairValueAdjustment


Operating
Period End2021-06-302021-03-312020-12-312020-09-302019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value5.86626-2.6554.10918-28.3261428262.9550.8483.6453.043-10.043-2.83615-0.7374.053-24.96125-10.74910-24.78645590.52878297.1662.361122416-1.9174.8754137-41.1284.08738
Percentage of OperatingPartnershipNoncontrollingInterestFairValueAdjustment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:OperatingPartnershipNoncontrollingInterestFairValueAdjustment us-gaap:ConsolidatedEntities

srt:Subsidiaries


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value5.86626-2.6554.109-7.3853818-28.3261428262.9550.8483.645
Percentage of OperatingPartnershipNoncontrollingInterestFairValueAdjustment100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:OriginationOfDebtAndPreferredEquityInvestments

slg:OriginationOfDebtAndPreferredEquityInvestments


Origination
Period End2021-06-302021-03-312020-06-302020-03-31
Value685.90542223
Percentage of OriginationOfDebtAndPreferredEquityInvestments100.0100.0100.0100.0

slg:OriginationOfDebtAndPreferredEquityInvestments us-gaap:ConsolidatedEntities

srt:Subsidiaries


Origination
Period End2021-06-302021-03-312020-06-302020-03-31
Value685.90542223
Percentage of OriginationOfDebtAndPreferredEquityInvestments100.0100.0100.0100.0

slg:OtherComprehensiveIncomeLossNetofTaxLessPortionAttributabletoNoncontrollingInterest us-gaap:ConsolidatedEntities

slg:OtherComprehensiveIncomeLossNetofTaxLessPortionAttributabletoNoncontrollingInterest

srt:Subsidiaries


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value-47.966486.171-1.503-52.383-11.737-24.39-19.1133.6774.0499.969
Percentage of OtherComprehensiveIncomeLossNetofTaxLessPortionAttributabletoNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:OtherComprehensiveIncomeLossNetofTaxLessPortionAttributabletoNoncontrollingInterest us-gaap:ConsolidatedEntities, us-gaap:StatementEquityComponents

srt:Subsidiaries, us-gaap:AccumulatedOtherComprehensiveIncome


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value-47.966486.171-1.503-52.383-11.737-24.39-19.1133.6774.0499.969
Percentage of OtherComprehensiveIncomeLossNetofTaxLessPortionAttributabletoNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:PartnersCapitalAccountValueUnitDividend us-gaap:ConsolidatedEntities

slg:PartnersCapitalAccountValueUnitDividend

srt:Subsidiaries


Partners
Period End2021-03-31
Value123
Percentage of PartnersCapitalAccountValueUnitDividend100.0

slg:PartnersCapitalAccountValueUnitDividend us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents

srt:Subsidiaries, us-gaap:GeneralPartner, us-gaap:CommonStock


Partners
Period End2021-03-31
Value123
Percentage of PartnersCapitalAccountValueUnitDividend100.0

slg:PaymentsForProceedsFromOtherInvestments

slg:PaymentsForProceedsFromOtherInvestments


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value4.0540.054-36.4-3.4032.5384.7865.3781.4350.01.056
Percentage of PaymentsForProceedsFromOtherInvestments100.0100.0100.0100.0100.0100.0100.0100.00.0100.0

slg:PaymentsForProceedsFromOtherInvestments us-gaap:ConsolidatedEntities

srt:Subsidiaries


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value4.0540.054-36.4-3.4032.5384.7865.3781.4350.01.056
Percentage of PaymentsForProceedsFromOtherInvestments100.0100.0100.0100.0100.0100.0100.0100.00.0100.0

slg:PaymentsForRepurchaseOfPartnershipUnits

slg:PaymentsForRepurchaseOfPartnershipUnits


Payments
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0.669130.8470.0180.0670.154150.00.00.0
Percentage of PaymentsForRepurchaseOfPartnershipUnits100.0100.0100.00.0100.0100.0100.0100.00.00.00.0

slg:PaymentsForRepurchaseOfPartnershipUnits us-gaap:ConsolidatedEntities

srt:Subsidiaries


Payments
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0.669130.8470.0180.0670.154150.00.00.0
Percentage of PaymentsForRepurchaseOfPartnershipUnits100.0100.0100.00.0100.0100.0100.0100.00.00.00.0

slg:PaymentsToAcquireLandBuildingsAndImprovements

slg:PaymentsToAcquireLandBuildingsAndImprovements


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value68491769881101102575339
Percentage of PaymentsToAcquireLandBuildingsAndImprovements100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:PaymentsToAcquireLandBuildingsAndImprovements us-gaap:ConsolidatedEntities

srt:Subsidiaries


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value68491769881101102575339
Percentage of PaymentsToAcquireLandBuildingsAndImprovements100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:PreferredStockConvertibleConversionRatio us-gaap:ConsolidatedEntities, us-gaap:StatementClassOfStock

slg:PreferredStockConvertibleConversionRatio

srt:Subsidiaries, us-gaap:SeriesAPreferredStock


Preferred
Period End2021-06-302021-03-312020-12-31
Value06.71350
Percentage of PreferredStockConvertibleConversionRatio0.0100.00.0

slg:ProceedsFromConsolidationOfRealEstateInvestment

slg:ProceedsFromConsolidationOfRealEstateInvestment


Proceeds
Period End2021-06-302021-03-31
Value09475000.0
Percentage of ProceedsFromConsolidationOfRealEstateInvestment0.0100.0

slg:ProceedsFromConsolidationOfRealEstateInvestment us-gaap:ConsolidatedEntities

srt:Subsidiaries


Proceeds
Period End2021-06-302021-03-31
Value09475000.0
Percentage of ProceedsFromConsolidationOfRealEstateInvestment0.0100.0

slg:ProceedsFromEquityMethodInvestmentDividendsOrDistributions

slg:ProceedsFromEquityMethodInvestmentDividendsOrDistributions


Proceeds
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3971928225317212329361421855537241066959.58403.51345771.118572228.6785.7845.333-79.366-4.338-27.52-16.652-4.606-5.664-6.385-95.704-37.76-4.821-2.184-8.155
Percentage of ProceedsFromEquityMethodInvestmentDividendsOrDistributions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:ProceedsFromEquityMethodInvestmentDividendsOrDistributions us-gaap:ConsolidatedEntities

srt:Subsidiaries


Proceeds
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value397192822531721232936142
Percentage of ProceedsFromEquityMethodInvestmentDividendsOrDistributions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:ProceedsFromNoncontrollingInterestsInOtherPartnerships

slg:ProceedsFromNoncontrollingInterestsInOtherPartnerships


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value0.1340.1710.0734.2184.3723.8145.3662.4042.3080.1610.5593.0721.6710.1573.0730.1931.062310.340.5850.50.9340.7433.2768.6550.02.742261.0310.5174.3830.4170.2543.116.7130.3820.46818
Percentage of ProceedsFromNoncontrollingInterestsInOtherPartnerships100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:ProceedsFromNoncontrollingInterestsInOtherPartnerships us-gaap:ConsolidatedEntities

srt:Subsidiaries


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.1340.1710.0734.2184.3723.8145.3662.4042.3080.1610.5593.0721.6710.157
Percentage of ProceedsFromNoncontrollingInterestsInOtherPartnerships100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships

slg:ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships


Profit
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-06-302011-03-31
Value109-5.2251861118361624791107105344112-2.402493814028107168-28.7425262702411514243302936171143453792
Percentage of ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Profit
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-06-302011-03-31
Value-0.04-1.4990.4141.023-0.293-0.624-2.1380.237-0.1360.1730.1982.478-1.4740.786-17.4911.3990.8363.4351.9742.6260.6646.6265.9271.5451.7121.8431.491.8232.9013.0042.901-1.2011.8343.8871.0713.2593.61
Percentage of ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships-0.028.72.31.7-0.2-1.7-1.30.5-0.10.20.27.2-3.66.2728.22.82.22.46.82.40.4-23.111.22.52.40.81.04.36.69.99.9-3.310.53.43.10.63.9

us-gaap:RetainedEarnings


Profit
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-06-302011-03-31
Value109-3.72617601183616447911071053142473713726105167-35.3684760682391494040272637151103353488
Percentage of ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships100.071.397.798.3100.2101.7101.399.5100.199.899.892.8103.697.297.897.693.297.699.6123.188.897.597.699.299.095.793.490.190.1103.389.596.696.999.496.1

slg:ProfitLossLessPreferredDistributions us-gaap:ConsolidatedEntities

slg:ProfitLossLessPreferredDistributions

srt:Subsidiaries


Profit
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value109-5.2251861118361624791107105
Percentage of ProfitLossLessPreferredDistributions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:ProfitLossLessPreferredDistributions us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents

srt:Subsidiaries, us-gaap:GeneralPartner, us-gaap:CommonStock


Profit
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value109-3.7261760118361644791107105
Percentage of ProfitLossLessPreferredDistributions100.071.397.798.3100.2101.7101.399.5100.199.899.8

slg:ProfitLossLessPreferredDistributions us-gaap:ConsolidatedEntities, us-gaap:StatementEquityComponents

srt:Subsidiaries, us-gaap:NoncontrollingInterest


Profit
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value-0.04-1.4990.4141.023-0.293-0.624-2.1380.237-0.1360.1730.198
Percentage of ProfitLossLessPreferredDistributions-0.028.72.31.7-0.2-1.7-1.30.5-0.10.20.2

slg:PurchasePriceFairValueAdjustmentGainLoss

slg:PurchasePriceFairValueAdjustmentGainLoss


Purchase
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value-1.9472.6640.00.00.03.79967-2.0410.0-3.057
Percentage of PurchasePriceFairValueAdjustmentGainLoss100.0100.00.00.00.0100.0100.0100.00.0100.0

slg:PurchasePriceFairValueAdjustmentGainLoss us-gaap:ConsolidatedEntities

srt:Subsidiaries


Purchase
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value-1.9472.6640.00.00.03.79967-2.0410.0-3.057
Percentage of PurchasePriceFairValueAdjustmentGainLoss100.0100.00.00.00.0100.0100.0100.00.0100.0

slg:PurchasePriceFairValueAdjustmentGross

slg:PurchasePriceFairValueAdjustmentGross


Purchase
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312015-12-312015-09-302015-06-302014-12-312014-09-302014-06-302013-12-312013-09-302013-06-302012-12-312012-09-302011-12-312011-09-302011-06-30
Value-1.9472.6640.00.00.03.79967-2.0410.0-3.05711490.00.00.00.0400.00.00.0-4.0710.00.0-2.3050.00.08.3060.999475
Percentage of PurchasePriceFairValueAdjustmentGross100.0100.00.00.00.0100.0100.0100.00.0100.0100.0100.00.00.00.00.0100.00.00.00.0100.0100.00.00.0100.00.00.0100.0100.0100.0

slg:PurchasePriceFairValueAdjustmentGross us-gaap:ConsolidatedEntities

srt:Subsidiaries


Purchase
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-1.9472.6640.00.00.03.79967-2.0410.0-3.0571149
Percentage of PurchasePriceFairValueAdjustmentGross100.0100.00.00.00.0100.0100.0100.00.0100.0100.0100.0

slg:ReallocationofNoncontrollingInterestInOperatingPartnershipIncreaseDecrease

slg:ReallocationofNoncontrollingInterestInOperatingPartnershipIncreaseDecrease


Reallocationof
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value-5.866-26.6094.109-7.38538-1.48114-28.932
Percentage of ReallocationofNoncontrollingInterestInOperatingPartnershipIncreaseDecrease100.0100.0100.0100.0100.0100.0100.0100.0

slg:ReallocationofNoncontrollingInterestInOperatingPartnershipIncreaseDecrease us-gaap:ConsolidatedEntities

srt:Subsidiaries


Reallocationof
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value-5.866-26.6094.109-7.38538-1.48114-28.932
Percentage of ReallocationofNoncontrollingInterestInOperatingPartnershipIncreaseDecrease100.0100.0100.0100.0100.0100.0100.0100.0

slg:ReallocationofNoncontrollingInterestInOperatingPartnershipIncreaseDecrease us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents

srt:Subsidiaries, us-gaap:GeneralPartner, us-gaap:CommonStock


Reallocationof
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value-5.866-26.6094.109-7.38538-1.48114-28.932
Percentage of ReallocationofNoncontrollingInterestInOperatingPartnershipIncreaseDecrease100.0100.0100.0100.0100.0100.0100.0100.0

slg:ReallocationofNoncontrollingInterestInOperatingPartnershipIncreaseDecrease us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Reallocationof
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value-5.866-26.6094.109-7.38538-1.48114-28.932
Percentage of ReallocationofNoncontrollingInterestInOperatingPartnershipIncreaseDecrease100.0100.0100.0100.0100.0100.0100.0100.0

slg:RemovalofFullyDepreciatedRealEstateAssets

slg:RemovalofFullyDepreciatedRealEstateAssets


Removalof
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value3.1681.12587.3720.0220.512120.8741.7164.0128.9294.7264.4521064.335.4043.7112.0439.2958.7088.6494.8222410.00.00.0
Percentage of RemovalofFullyDepreciatedRealEstateAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.0

slg:RemovalofFullyDepreciatedRealEstateAssets us-gaap:ConsolidatedEntities

srt:Subsidiaries


Removalof
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value3.1681.12587.3720.0220.512120.8741.7164.0128.9294.7264.452106
Percentage of RemovalofFullyDepreciatedRealEstateAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:RentalRevenueIncreaseDecreaseAcquiredLeaseAmortization

slg:RentalRevenueIncreaseDecreaseAcquiredLeaseAmortization


Rental
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value-1.91.91.41.61.61.20.91.21.21.21.31.31.82.44.54.66.44.84.8-0.2156345.8108.3145.15.76.24.85.0-0.26.23.93.02.62.72.14.23.45.07.23.86.16.2
Percentage of RentalRevenueIncreaseDecreaseAcquiredLeaseAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:RepaymentsOrRedemptionOfDebtAndPreferredEquityInvestments

slg:RepaymentsOrRedemptionOfDebtAndPreferredEquityInvestments


Repayments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value5964487151449315108218
Percentage of RepaymentsOrRedemptionOfDebtAndPreferredEquityInvestments100.0100.0100.0100.0100.0100.0100.0100.0

slg:RepaymentsOrRedemptionOfDebtAndPreferredEquityInvestments us-gaap:ConsolidatedEntities

srt:Subsidiaries


Repayments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value5964487151449315108218
Percentage of RepaymentsOrRedemptionOfDebtAndPreferredEquityInvestments100.0100.0100.0100.0100.0100.0100.0100.0

slg:ReversalOfAssetsHeldForSale

slg:ReversalOfAssetsHeldForSale


Reversal
Period End2020-12-312020-09-302020-06-302020-03-312019-06-302019-03-31
Value0.00.00.03910.00.0
Percentage of ReversalOfAssetsHeldForSale0.00.00.0100.00.00.0

slg:ReversalOfAssetsHeldForSale us-gaap:ConsolidatedEntities

srt:Subsidiaries


Reversal
Period End2020-12-312020-09-302020-06-302020-03-312019-06-302019-03-31
Value0.00.00.03910.00.0
Percentage of ReversalOfAssetsHeldForSale0.00.00.0100.00.00.0

slg:SECSchedule1229RealEstateCompaniesInvestmentInMortgageLoansOnRealEstateLoanLossReservePeriodIncreaseDecrease

slg:SECSchedule1229RealEstateCompaniesInvestmentInMortgageLoansOnRealEstateLoanLossReservePeriodIncreaseDecrease


S
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value5797000.0-3901000.022848000.0-36207000.00004000000.0
Percentage of SECSchedule1229RealEstateCompaniesInvestmentInMortgageLoansOnRealEstateLoanLossReservePeriodIncreaseDecrease100.0100.0100.0100.00.00.00.0100.0

slg:SellerFinancedPurchases

slg:SellerFinancedPurchases


Seller
Period End2020-12-312020-09-302020-06-302020-03-312019-06-302019-03-31
Value0.00.00.01000.00.0
Percentage of SellerFinancedPurchases0.00.00.0100.00.00.0

slg:SellerFinancedPurchases us-gaap:ConsolidatedEntities

srt:Subsidiaries


Seller
Period End2020-12-312020-09-302020-06-302020-03-312019-06-302019-03-31
Value0.00.00.01000.00.0
Percentage of SellerFinancedPurchases0.00.00.0100.00.00.0

slg:ShareBasedCompensationArrangementByShareBasedPaymentAwardGrantsInPeriodFairValue us-gaap:AwardType

slg:ShareBasedCompensationArrangementByShareBasedPaymentAwardGrantsInPeriodFairValue

slg:LongTermIncentivePlanUnits


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312012-12-31
Value-0.2403.3-0.7-0.234160.00.0411.40.00.0200.00.00.0206.80.00.7270.00.00.0259.62.41.5190.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardGrantsInPeriodFairValue100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.00.00.0100.00.00.00.0100.0100.00.0100.0100.00.00.00.0100.0100.0100.0100.0100.00.0

slg:RestrictedStockAwards


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302012-12-31
Value0.09.2145310.00.00.0464760.6878398.8976331.7590680.00.474481.0582-3.0731753.2370060.00.0308130.09.0362310.8325160.687490.09384150.343740.0581180.3331531.1416750.00.00.0160.5728876.895066
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardGrantsInPeriodFairValue-0.022.90.0-0.0-23.22.053.30.00.01.10.00.015.70.00.00.0132.90.098.20.30.00.00.01.311.90.00.00.00.00.00.0

slg:ShareRepurchasesPayable

slg:ShareRepurchasesPayable


Share
Period End2021-06-302021-03-312020-12-312020-09-302019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value163.779-6.2241.183-8.8398.8390.00.0-41.746103.672741-41.598410.0
Percentage of ShareRepurchasesPayable100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.00.0

slg:ShareRepurchasesPayable us-gaap:ConsolidatedEntities

srt:Subsidiaries


Share
Period End2021-06-302021-03-312020-12-312020-09-302019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value163.779-6.2241.183-8.8398.8390.00.0-41.746103.6727
Percentage of ShareRepurchasesPayable100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0

slg:TotalCostsAndExpensesIncludingNonoperatingIncomeExpense

slg:TotalCostsAndExpensesIncludingNonoperatingIncomeExpense


Total
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value196207213248249247252263258260267265258258314333365332347369693456370414442358347344336335343336323327342342316316311293276263269239238241
Percentage of TotalCostsAndExpensesIncludingNonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:TotalCostsAndExpensesIncludingNonoperatingIncomeExpense us-gaap:ConsolidatedEntities

srt:Subsidiaries


Total
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value196207213248249247252263258260267265258258314333365332
Percentage of TotalCostsAndExpensesIncludingNonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:TotalCostsAndExpensesIncludingNonoperatingIncomeExpense us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Total
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value305306305296276301301308308320317311321321241206211211
Percentage of TotalCostsAndExpensesIncludingNonoperatingIncomeExpense155.8147.7143.0119.3110.7121.9119.3117.2119.5123.1118.5117.4124.3124.376.761.757.963.4

slg:TransactionRelatedCosts

slg:TransactionRelatedCosts


Transaction
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.0030.0220.0450.3730.0650.0440.2610.0550.1630.3480.1620.1860.0460.1331.5412.5932.1151.2791.3915.8293.0671.1432.1532.3831.6972.4743.268-2.3491.7111.3581.1321.3721.971.1511.7410.1691.2172.4343.4333.2544.1041.058
Percentage of TransactionRelatedCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:TransactionRelatedCosts us-gaap:ConsolidatedEntities

srt:Subsidiaries


Transaction
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0.0030.0220.0450.3730.0650.0440.2610.0550.1630.3480.162
Percentage of TransactionRelatedCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:UnitDividendsUnits us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents

slg:UnitDividendsUnits

srt:Subsidiaries, us-gaap:GeneralPartner, us-gaap:CommonStock


Unit
Period End2021-03-31
Value2034000.0
Percentage of UnitDividendsUnits100.0

slg:WeightedAverageNumberofUnitsOutstandingDiluted us-gaap:ConsolidatedEntities

slg:WeightedAverageNumberofUnitsOutstandingDiluted

srt:Subsidiaries


Weighted
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value7374778082868787909295
Percentage of WeightedAverageNumberofUnitsOutstandingDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

srt:MortgageLoansOnRealEstateInterestRate

srt:MortgageLoansOnRealEstateInterestRate


Mortgage
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.615.9-0.466.17720.00410.0787-0.0047-0.00110.00210.0879
Percentage of MortgageLoansOnRealEstateInterestRate100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

srt:MortgageLoansOnRealEstateInterestRate us-gaap:MortgageLoansOnRealEstateLoanType

slg:PreferredEquityInvestmentsInMortgageLoans


Mortgage
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-0.029.94-0.029.880.00130.09870.001200.00770.0874
Percentage of MortgageLoansOnRealEstateInterestRate-3.3168.54.3159.931.7125.4-25.5-0.0366.799.4

us-gaap:AffiliateCosts

us-gaap:AffiliateCosts


Affiliate
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3.0392.2252.8012.7393.7495.465.3232.7934.794.6553.8345.5055.2624.1736.7195.0426.6673.4626.6565.2384.4723.8086.1255.1044.453.4115.3834.8764.3194.155.2454.6684.7293.4595.1784.3353.4983.1154.6623.3913.0773.104
Percentage of AffiliateCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AffiliateCosts us-gaap:ConsolidatedEntities

srt:Subsidiaries


Affiliate
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value3.0392.2252.8012.7393.7495.465.3232.7934.794.6653.834
Percentage of AffiliateCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.2100.0

us-gaap:AmortizationOfAboveAndBelowMarketLeases

us-gaap:AmortizationOfAboveAndBelowMarketLeases


Amortization
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-1892000.0-1869000.01362000.01670000.01630000.01239000.0915000.01165000.01185000.01209000.01332000.01320000.01804000.02362000.0
Percentage of AmortizationOfAboveAndBelowMarketLeases100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AssetImpairmentCharges us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

us-gaap:AssetImpairmentCharges

slg:East400Street57


Asset
Period End2021-04-30
Value5.7
Percentage of AssetImpairmentCharges100.0

us-gaap:AssetImpairmentCharges us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations, us-gaap:SubsequentEventType

slg:East400Street57, us-gaap:SubsequentEvent


Asset
Period End2021-04-30
Value5.7
Percentage of AssetImpairmentCharges100.0

us-gaap:AssetImpairmentCharges us-gaap:StatementGeographical

slg:A106SpringStreetMember


Asset
Period End2020-12-31
Value39
Percentage of AssetImpairmentCharges0.0

slg:A133GreeneStreet


Asset
Period End2020-12-31
Value14
Percentage of AssetImpairmentCharges0.0

us-gaap:AssetsFairValueAdjustment us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

us-gaap:AssetsFairValueAdjustment

slg:OneMadisonAvenue


Assets
Period End2021-06-302021-03-31
Value0.02.7
Percentage of AssetsFairValueAdjustment0.0100.0

us-gaap:AvailableForSaleDebtSecuritiesGrossUnrealizedLoss us-gaap:FinancialInstrument

us-gaap:AvailableForSaleDebtSecuritiesGrossUnrealizedLoss

us-gaap:CommercialMortgageBackedSecurities


Available
Period End2021-06-302021-03-31
Value-100000.0700000.0
Percentage of AvailableForSaleDebtSecuritiesGrossUnrealizedLoss100.0100.0

us-gaap:CapitalExpendituresIncurredButNotYetPaid

us-gaap:CapitalExpendituresIncurredButNotYetPaid


Capital
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value-6.30315-10.3285.346.0510.602-3.9841.019-0.3299.35-16.246-0.2880.58215-2.2591.7160.1237.08711-7.356-6.52818-6.715-3.191-0.003170.9521.264-2.7069.898-9.3530.190.5299.136-8.318-2.2380.35311-4.6960.2970.8967.493-5.640.258
Percentage of CapitalExpendituresIncurredButNotYetPaid100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CapitalExpendituresIncurredButNotYetPaid us-gaap:ConsolidatedEntities

srt:Subsidiaries


Capital
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-6.30315-10.3285.346.0510.602-3.9841.019-0.3299.35-16.246-0.2880.58215
Percentage of CapitalExpendituresIncurredButNotYetPaid100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths

us-gaap:CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths


Cash
Period End2021-06-302021-03-31
Value-0.300000000000001916
Percentage of CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths100.0100.0

us-gaap:CommonStockDividendsPerShareCashPaid slg:DividendType, us-gaap:StatementEquityComponents

us-gaap:CommonStockDividendsPerShareCashPaid

slg:CashDividend, us-gaap:CommonStock


Common
Period End2021-01-15
Value0.3735
Percentage of CommonStockDividendsPerShareCashPaid100.0

us-gaap:ConcentrationRiskPercentage1 slg:RealEstateByLocation, us-gaap:ConcentrationRiskByBenchmark, us-gaap:ConcentrationRiskByType

us-gaap:ConcentrationRiskPercentage1

slg:A11MadisonAve, slg:AnnualizedRent, us-gaap:CustomerConcentrationRisk


Concentration
Period End2021-03-312020-03-312019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302016-03-312015-09-30
Value9.20.0830.0740.0720.0730.0730.0630.0580.0970.067
Percentage of ConcentrationRiskPercentage1100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

slg:AvenueOfTheAmericas1185, slg:AnnualizedRent, us-gaap:CustomerConcentrationRisk


Concentration
Period End2021-03-312020-03-312019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-03-312015-09-302015-06-302015-03-312014-03-312013-09-302013-06-302013-03-312012-09-30
Value7.10.0850.0670.0620.0720.0730.0620.0630.0630.0660.070.0750.0770.0740.070.060.070.06
Percentage of ConcentrationRiskPercentage177.2102.490.586.198.6100.098.4108.60.068.0104.50.00.00.00.00.00.00.0

slg:Broadway1515, slg:AnnualizedRent, us-gaap:CustomerConcentrationRisk


Concentration
Period End2021-03-312020-03-312019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-03-312015-09-302015-06-302015-03-312014-03-312013-09-302013-06-302013-03-312012-09-30
Value6.90.0680.060.0580.0580.0580.0890.0850.0810.0910.0970.1010.1010.0970.10.090.090.1
Percentage of ConcentrationRiskPercentage175.081.981.180.679.579.5141.3146.60.093.8144.80.00.00.00.00.00.00.0

slg:East220Street42, slg:AnnualizedRent, us-gaap:CustomerConcentrationRisk


Concentration
Period End2021-03-312020-03-31
Value6.20.062
Percentage of ConcentrationRiskPercentage167.474.7

slg:LexingtonAvenue420, slg:AnnualizedRent, us-gaap:CustomerConcentrationRisk


Concentration
Period End2021-03-312020-03-312019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-03-312015-09-302013-03-312012-09-30
Value7.20.0750.0630.0640.0640.0630.0540.0560.0540.0570.0570.060.05
Percentage of ConcentrationRiskPercentage178.390.485.188.987.786.385.796.60.058.885.10.00.0

slg:LexingtonAvenue485, slg:AnnualizedRent, us-gaap:CustomerConcentrationRisk


Concentration
Period End2021-03-312020-03-312012-09-30
Value5.10.0530.05
Percentage of ConcentrationRiskPercentage155.463.90.0

slg:ParkAvenue280, slg:AnnualizedRent, us-gaap:CustomerConcentrationRisk


Concentration
Period End2021-03-312020-03-31
Value5.80.054
Percentage of ConcentrationRiskPercentage163.065.1

us-gaap:ConcentrationRiskPercentage1 us-gaap:MajorCustomers, us-gaap:ConcentrationRiskByBenchmark, us-gaap:ConcentrationRiskByType

slg:Tenant1, slg:AnnualizedRent, us-gaap:CustomerConcentrationRisk


Concentration
Period End2021-03-312020-03-312019-03-31
Value5.90.0550.082
Percentage of ConcentrationRiskPercentage164.166.3110.8

us-gaap:DepreciationAndAmortization

us-gaap:DepreciationAndAmortization


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value57625692956864706968717067698491133941041124251791061461991089794948989878280938377777473656773565559
Percentage of DepreciationAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DepreciationAndAmortization us-gaap:ConsolidatedEntities

srt:Subsidiaries


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value5762569295686470696871706769
Percentage of DepreciationAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DepreciationAndAmortization us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value11611410710398989810010310410310111110580616571
Percentage of DepreciationAndAmortization204.3182.4188.2111.6103.0144.4154.4143.0149.3152.7144.6143.5164.2151.495.867.049.675.6

us-gaap:DilutiveSecuritiesEffectOnBasicEarningsPerShareOther

us-gaap:DilutiveSecuritiesEffectOnBasicEarningsPerShareOther


Dilutive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value6.282-0.4769.9430.8023.076.2020.9951.7198.312.2780.2440.5550.7210.5673.4210.8880.6830.169111.8520.031.7862.467
Percentage of DilutiveSecuritiesEffectOnBasicEarningsPerShareOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

us-gaap:DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax

slg:A106SpringStreetMember


Discontinued
Period End2021-03-31
Value-2.8
Percentage of DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax100.0

slg:A133GreeneStreet


Discontinued
Period End2021-02-28
Value0.2
Percentage of DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax0.0

slg:A30East40thStreet


Discontinued
Period End2020-12-31
Value-1.6
Percentage of DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax0.0

slg:A410TenthAvenue


Discontinued
Period End2020-12-31
Value56
Percentage of DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax0.0

slg:A635641SixthAvenue


Discontinued
Period End2021-06-30
Value99
Percentage of DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax0.0

slg:A712MadisonAvenue


Discontinued
Period End2021-01-31
Value-1.4
Percentage of DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax0.0

slg:East400Street58


Discontinued
Period End2020-09-30
Value8.3
Percentage of DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax0.0

slg:WashingtonBoulevard1055


Discontinued
Period End2020-12-31
Value-11.5
Percentage of DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax0.0

slg:Williamsburg


Discontinued
Period End2020-12-31
Value11
Percentage of DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax0.0

us-gaap:DistributedEarnings

us-gaap:DistributedEarnings


Distributed
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-30
Value369000.0371000.0333000.0333000.0113000.0108000.0128000.0
Percentage of DistributedEarnings100.0100.0100.0100.0100.0100.0100.0

us-gaap:DistributedEarnings us-gaap:ConsolidatedEntities

srt:Subsidiaries


Distributed
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value369000.0371000.0910000.0333000.0333000.0113000.01414000.0108000.0128000.0124000.0181000.0125000.0119000.0109000.0
Percentage of DistributedEarnings100.0100.00.0100.0100.0100.00.0100.0100.00.00.00.00.00.0

us-gaap:DividendsCommonStock

us-gaap:DividendsCommonStock


Dividends
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value6263646622696970696972757576777872727171595959584747474829303030222222218.588.4348.137
Percentage of DividendsCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DividendsCommonStock us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Dividends
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value6263646622696970696972757576777872727171595959584747474829303030222222218.588.4348.137
Percentage of DividendsCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DividendsPreferredStock

us-gaap:DividendsPreferredStock


Dividends
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3.7373.7383.7373.7383.7373.7383.7373.7383.7373.7383.7373.7383.7373.7383.7373.7383.7373.7383.7373.7383.7373.7383.7383.7383.7383.7383.7383.7383.7383.7383.7373.7386.9997.4077.4077.9157.5447.9427.5437.5457.5457.5457.5457.5457.5457.114
Percentage of DividendsPreferredStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DividendsPreferredStock us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Dividends
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value3.7373.7383.7383.7373.7383.7383.7373.7383.7383.7373.7383.7373.7383.7373.7383.7373.7383.7373.7383.7383.7383.7383.7383.7383.7393.7373.7383.7373.7386.9997.4077.4077.9157.1477.9427.5447.5457.5447.545
Percentage of DividendsPreferredStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.094.7100.0100.0100.0100.0100.0

us-gaap:EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount

us-gaap:EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount


Employee
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value0.50.50.50.60.60.60.70.50.50.51.61.61.61.62.21.42.01.61.61.51.41.51.61.51.81.61.61.71.91.61.60.91.01.01.20.91.01.00.60.90.91.00.50.50.6
Percentage of EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EquityMethodInvestmentDividendsOrDistributions

us-gaap:EquityMethodInvestmentDividendsOrDistributions


Equity
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.1050.0690.1030.370.0980.1080.2160.0820.1410.4250.1030.2852.3797.510.77.2216.925.4685.0264.0516.3698.8917.618106.975155.7948.426.9767.669138.2566.5666.9016.9636.201734.4081.3981.9214.9512.9158.0493.4585.63710
Percentage of EquityMethodInvestmentDividendsOrDistributions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EquityMethodInvestmentDividendsOrDistributions us-gaap:ConsolidatedEntities

srt:Subsidiaries


Equity
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.1050.0690.1030.370.0980.1080.2160.0820.1410.4250.1030.2852.3797.51
Percentage of EquityMethodInvestmentDividendsOrDistributions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EquityMethodInvestmentRealizedGainLossOnDisposal

us-gaap:EquityMethodInvestmentRealizedGainLossOnDisposal


Equity
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302010-12-312010-09-302010-06-30
Value8.471-12.6290.00.00.00.059171677072-6.440.01.03132.0470.4210.225339.915-0.206150.7690.00.673161.4441047.538-0.354-3.5830.019-4.8079.5347.26-0.1143.0321.6330.52126
Percentage of EquityMethodInvestmentRealizedGainLossOnDisposal100.0100.00.00.00.00.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EquityMethodInvestmentRealizedGainLossOnDisposal us-gaap:ConsolidatedEntities

srt:Subsidiaries


Equity
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value8.471-12.6290.00.00.00.059171677072-6.440.01.03132.047
Percentage of EquityMethodInvestmentRealizedGainLossOnDisposal100.0100.00.00.00.00.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0

us-gaap:EquityMethodInvestmentRealizedGainLossOnDisposal us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations, us-gaap:RelatedPartyTransactionsByRelatedParty

slg:A333East22ndSt, us-gaap:CorporateJointVenture


Equity
Period End2020-12-31
Value2.968
Percentage of EquityMethodInvestmentRealizedGainLossOnDisposal0.0

slg:A55West46thStreetTower46, us-gaap:CorporateJointVenture


Equity
Period End2021-06-302021-03-31
Value0.0089-0.0152
Percentage of EquityMethodInvestmentRealizedGainLossOnDisposal0.10.1

us-gaap:EquityMethodInvestmentSummarizedFinancialInformationNetIncomeLoss us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:EquityMethodInvestmentSummarizedFinancialInformationNetIncomeLoss

us-gaap:CorporateJointVenture


Equity
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-3.125-5.056-18.525-22.048-23.587-18.443-12.912-12.412-6.891-6.949-0.189192.4-1.0665.451
Percentage of EquityMethodInvestmentSummarizedFinancialInformationNetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EquityMethodInvestmentSummarizedFinancialInformationRevenue us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:EquityMethodInvestmentSummarizedFinancialInformationRevenue

us-gaap:CorporateJointVenture


Equity
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value292271282279286290307304304314320261216210216
Percentage of EquityMethodInvestmentSummarizedFinancialInformationRevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinanceLeaseInterestExpense

us-gaap:FinanceLeaseInterestExpense


Finance
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value1494000.01492000.02081000.01610000.01106000.01663000.0818000.0813000.0808000.0804000.08069000.000786000.0
Percentage of FinanceLeaseInterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.0

us-gaap:FinanceLeasePrincipalPayments

us-gaap:FinanceLeasePrincipalPayments


Finance
Period End2021-06-302021-03-312020-12-312020-09-30
Value179000.0255000.0253000.0250000.0
Percentage of FinanceLeasePrincipalPayments100.0100.0100.0100.0

us-gaap:FinanceLeasePrincipalPayments us-gaap:ConsolidatedEntities

srt:Subsidiaries


Finance
Period End2021-06-302021-03-312020-12-312020-09-30
Value179000.0255000.0253000.0250000.0
Percentage of FinanceLeasePrincipalPayments100.0100.0100.0100.0

us-gaap:FinanceLeaseRightOfUseAssetAmortization

us-gaap:FinanceLeaseRightOfUseAssetAmortization


Finance
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value180000.0180000.0286000.0304000.0305000.0300000.0305000.0304000.0305000.0300000.0
Percentage of FinanceLeaseRightOfUseAssetAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancingReceivableAllowanceForCreditLossesWriteOffs us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

us-gaap:FinancingReceivableAllowanceForCreditLossesWriteOffs

slg:InvestmentsSoldIn2020


Financing
Period End2020-12-31
Value19
Percentage of FinancingReceivableAllowanceForCreditLossesWriteOffs100.0

us-gaap:GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes

us-gaap:GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes


Gain
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value266472-19.2413.5410.0-1.049-36.984-2.504-14.7923
Percentage of GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0

us-gaap:GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes us-gaap:ConsolidatedEntities

srt:Subsidiaries


Gain
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value266472-19.2413.5410.0-1.049-36.984-2.504-14.7923
Percentage of GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0

us-gaap:GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes us-gaap:StatementGeographical

slg:A126NassauStreet


Gain
Period End2020-08-31
Value17
Percentage of GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes0.0

us-gaap:GainsLossesOnSalesOfInvestmentRealEstate

us-gaap:GainsLossesOnSalesOfInvestmentRealEstate


Gains
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-30
Value98-1.38851266472-19.2413.5410.0-1.049-36.984-2.504-14.7923760.0-3.8230.567270.39719613161590.00.00.00.0
Percentage of GainsLossesOnSalesOfInvestmentRealEstate100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0

us-gaap:GainsLossesOnSalesOfInvestmentRealEstate us-gaap:ConsolidatedEntities

srt:Subsidiaries


Gains
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value98-1.38851266472-19.2413.5410.0-1.049-36.984-2.504-14.7923760.0-3.8230.567
Percentage of GainsLossesOnSalesOfInvestmentRealEstate100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.00.0100.0100.0

us-gaap:GainsLossesOnSalesOfInvestmentRealEstate us-gaap:StatementGeographical

slg:A126NassauStreet


Gains
Period End2020-08-31
Value17
Percentage of GainsLossesOnSalesOfInvestmentRealEstate0.0

us-gaap:GainsLossesOnSalesOfInvestmentRealEstate us-gaap:StatementGeographical, us-gaap:StatementScenario, us-gaap:RelatedPartyTransactionsByRelatedParty

slg:West46thStreet55, srt:ScenarioForecast, us-gaap:CorporateJointVenture


Gains
Period End2021-03-31
Value-17.8
Percentage of GainsLossesOnSalesOfInvestmentRealEstate1282.4

us-gaap:IncomeLossFromEquityMethodInvestments

us-gaap:IncomeLossFromEquityMethodInvestments


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-12.97-2.864-9.75-0.432-2.199-12.814-11.874-9.864-7.546-5.234-2.3980.9714.7024.0367.7884.0783.4126.614-0.095-3.9685.841102.3773.6272.9944.035.7566.0348.6196.1285.672.939-3.7615.073-4.571170-1.56-6.08-2.7282.1848.2066.6827.5441015
Percentage of IncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeLossFromEquityMethodInvestments us-gaap:ConsolidatedEntities

srt:Subsidiaries


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-12.97-2.864-9.75-0.432-2.199-12.814-11.874-9.864-7.546-5.234-2.3980.9714.7024.0367.7884.0783.4126.614
Percentage of IncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeLossFromEquityMethodInvestments us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-12.97-2.864-9.75-0.432-2.199-12.814-11.874-9.864-7.546-5.234-2.3980.9714.7024.0367.7884.0783.4126.614
Percentage of IncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInDeferredLeasingFees

us-gaap:IncreaseDecreaseInDeferredLeasingFees


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3.3620.248.4281.3292.548.603326.359191312149.797.679107.919149.4212315181314102411356.8566.2124.476239.396144.646109.336217.15212106.8837.65114135.8417.934
Percentage of IncreaseDecreaseInDeferredLeasingFees100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInDeferredLeasingFees us-gaap:ConsolidatedEntities

srt:Subsidiaries


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value3.3620.248.4281.3292.548.603326.359191312149.797.679
Percentage of IncreaseDecreaseInDeferredLeasingFees100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInDeferredLiabilities

us-gaap:IncreaseDecreaseInDeferredLiabilities


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-3.2334.1217.45116-11.1257.622-7.43118-11.14810-5.2916-3.5714.692-8.754253.87125-17.77922-21.22217-18.57620-11.18414-14.58120-11.84714-15.57414-11.49419-8.77414-9.7557.62-6.42415-6.1573.073-7.469.042-5.5281.704
Percentage of IncreaseDecreaseInDeferredLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInDeferredLiabilities us-gaap:ConsolidatedEntities

srt:Subsidiaries


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-3.2334.1217.45116-11.1257.622-7.43118-11.14810-5.2916-3.5714.692
Percentage of IncreaseDecreaseInDeferredLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInDueFromRelatedPartiesCurrent

us-gaap:IncreaseDecreaseInDueFromRelatedPartiesCurrent


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1.3720.6832.7440.2-9.1064.7111.119-4.44-5.7511.276.23-6.302-3.4514.567-1.0290.3694.6583.2111.0161.781-2.1174.503-0.632-0.306-0.6930.353-1.5274.347-11.032110.730.955-4.4063.638-0.2630.00.1283.664-1.9370.6331.292-2.449-0.7891.0622.681-5.352
Percentage of IncreaseDecreaseInDueFromRelatedPartiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInDueFromRelatedPartiesCurrent us-gaap:ConsolidatedEntities

srt:Subsidiaries


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value1.3720.6832.7440.2-9.1064.7111.119-4.44-5.7511.276.23-6.302-3.4514.567
Percentage of IncreaseDecreaseInDueFromRelatedPartiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInOtherOperatingAssets

us-gaap:IncreaseDecreaseInOtherOperatingAssets


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-39.90424-29.16437-30.76748-28.50946-39.92340-43.86247-43.49747-35.058-46.03645-40.79835-51.09846-62.23755-49.6938-45.05735-32.51132-26.2227-25.2621-8.983172.94624-16.02317-12.1837.014-6.26413-13.2431.134
Percentage of IncreaseDecreaseInOtherOperatingAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInOtherOperatingAssets us-gaap:ConsolidatedEntities

srt:Subsidiaries


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-39.90424-29.16437-30.76748-28.50946-39.92340-43.86247-43.49747
Percentage of IncreaseDecreaseInOtherOperatingAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends

us-gaap:IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends


Incremental
Period End2021-06-302021-03-31
Value-160000.0317000.0
Percentage of IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends100.0100.0

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements


Incremental
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value654000.0595000.0-1000.0442000.0409000.0483000.0383000.0164000.0167000.0164000.04000.0219000.0201000.053000.0-3000.0244000.0270000.0304000.024000.0413000.0316000.0234000.010000.0407000.00653000.0-54000.0387000.0514000.0520000.020000.0236000.0224000.0216000.0-21000.0330000.0369000.0380000.0-10000.0473000.0520000.0437000.0-4000.0344000.0420000.0
Percentage of IncrementalCommonSharesAttributableToShareBasedPaymentArrangements100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestCostsIncurredCapitalized

us-gaap:InterestCostsIncurredCapitalized


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value20171720162017151210118.5047.5946.6866.8696.7436.2795.9326.0845.4336.6187.6127.3277.6118.5584.0617.9726.8624.1412.2842.8283.3013.0623.3263.362.9962.5361.4941.4120.9221.295
Percentage of InterestCostsIncurredCapitalized100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet

us-gaap:InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value6.6056.0886.5236.6164.9041.4361.6040.297-0.992-0.903-0.901-0.533-0.231-0.33-0.397-0.27-0.811-1.378-1.964-1.989-5.035-2.514-2.987-3.024-3.068-3.0782.771.8671.8281.9651.9661.6011.73-1.708-2.992-3.249-3.215-3.201-3.231-3.179-3.145-3.094-3.256-3.161-3.185
Percentage of InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet us-gaap:DerivativeInstrumentRisk

us-gaap:InterestRateSwap


Interest
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value4.5554.3885.1623.7220.7250.105-0.456-0.535-0.295-0.076-0.329-0.085-0.519-0.979-1.448-1.442-4.468-2.163-2.671-2.737-2.737-2.7472.6411.8261.2720.6920.6750.320.470.468
Percentage of InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet69.072.178.075.950.535.446.059.255.332.999.731.564.071.073.772.588.786.089.490.589.289.295.397.869.635.234.320.027.2-27.4

us-gaap:InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value2.051.71.5641.4541.1820.7110.4570.192-0.536-0.368-0.334-0.238-0.155-0.001-1.9110.1850.292-0.399
Percentage of InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet31.027.924.022.024.149.528.564.654.040.837.144.767.10.3481.4-68.5-36.029.0

us-gaap:InvestmentIncomeInterestAndDividend

us-gaap:InvestmentIncomeInterestAndDividend


Investment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value20191822393842515150574849454547604038754454444945424143395449444652312733262218156722842020
Percentage of InvestmentIncomeInterestAndDividend100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InvestmentIncomeInterestAndDividend us-gaap:ConsolidatedEntities

srt:Subsidiaries


Investment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value2019182239384251515057484945
Percentage of InvestmentIncomeInterestAndDividend100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:MarketableSecuritiesUnrealizedGainLoss

us-gaap:MarketableSecuritiesUnrealizedGainLoss


Marketable
Period End2021-06-30
Value-1900000.0
Percentage of MarketableSecuritiesUnrealizedGainLoss100.0

us-gaap:MinorityInterestDecreaseFromRedemptions us-gaap:ConsolidatedEntities

us-gaap:MinorityInterestDecreaseFromRedemptions

srt:PartnershipInterest


Minority
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value28138.4280.8478.6618
Percentage of MinorityInterestDecreaseFromRedemptions100.0100.0100.0100.0100.0100.0

us-gaap:MinorityInterestDecreaseFromRedemptions us-gaap:ConsolidatedEntities, us-gaap:StatementClassOfStock

srt:Subsidiaries, us-gaap:PreferredStock


Minority
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.03.6310.02240193.00.00.015
Percentage of MinorityInterestDecreaseFromRedemptions0.027.40.02709.6466.6106.80.00.00.00.0

us-gaap:MortgageLoansOnRealEstateAmortizationOfPremium

us-gaap:MortgageLoansOnRealEstateAmortizationOfPremium


Mortgage
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value91161633161457316146271186246297263105
Percentage of MortgageLoansOnRealEstateAmortizationOfPremium100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:MortgageLoansOnRealEstateNewMortgageLoans us-gaap:InvestmentType

us-gaap:MortgageLoansOnRealEstateNewMortgageLoans

slg:DebtInvestmentsInMortgageLoans


Mortgage
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value72175.9359443246
Percentage of MortgageLoansOnRealEstateNewMortgageLoans100.0100.0100.0100.0100.0100.0

slg:PreferredEquityInvestmentsInMortgageLoans


Mortgage
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value3.2743.1953.2213.1765.935154
Percentage of MortgageLoansOnRealEstateNewMortgageLoans4.518.354.33.413.762.9

us-gaap:NetIncomeLossNetOfTaxPerOutstandingLimitedPartnershipUnitDiluted us-gaap:ConsolidatedEntities

us-gaap:NetIncomeLossNetOfTaxPerOutstandingLimitedPartnershipUnitDiluted

srt:Subsidiaries


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value1.51-0.112.430.190.741.470.210.41.940.52-0.731.031.191.120.290.40.080.11
Percentage of NetIncomeLossNetOfTaxPerOutstandingLimitedPartnershipUnitDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NetIncomeLossPerOutstandingLimitedPartnershipUnitBasicNetOfTax us-gaap:ConsolidatedEntities

us-gaap:NetIncomeLossPerOutstandingLimitedPartnershipUnitBasicNetOfTax

srt:Subsidiaries


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value1.52-0.112.440.190.741.470.210.41.940.52-0.731.031.191.120.290.40.080.11
Percentage of NetIncomeLossPerOutstandingLimitedPartnershipUnitBasicNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NoncontrollingInterestInNetIncomeLossOperatingPartnershipsRedeemable

us-gaap:NoncontrollingInterestInNetIncomeLossOperatingPartnershipsRedeemable


Noncontrolling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value6.282-0.4769.9430.8023.076.2020.9951.7198.312.278-3.444.7975.5865.2721.2881.8120.4190.4761.9651.6635.5860.9223.9316.467-1.5771.7432.4572.6368.6454.7291.1141.110.2440.555
Percentage of NoncontrollingInterestInNetIncomeLossOperatingPartnershipsRedeemable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NoncontrollingInterestInNetIncomeLossOperatingPartnershipsRedeemable us-gaap:ConsolidatedEntities

srt:PartnershipInterest


Noncontrolling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value6.282-0.4769.9430.8013.076.202
Percentage of NoncontrollingInterestInNetIncomeLossOperatingPartnershipsRedeemable100.0100.0100.099.9100.0100.0

us-gaap:NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable

us-gaap:NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable


Noncontrolling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value-0.04-1.499130.4141.023-0.293-0.635-0.624-2.1380.237-0.24-0.1360.1730.1982.478-1.4740.786-17.4911.3990.8363.4351.9742.6260.6656.6265.9271.5451.7121.8431.491.8232.9013.0042.901
Percentage of NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable us-gaap:ConsolidatedEntities

srt:Subsidiaries


Noncontrolling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-0.04-1.499130.4141.023-0.293-0.635-0.624-2.1380.237-0.24-0.1360.1730.198
Percentage of NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable

us-gaap:NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable


Noncontrolling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value1.8231.8461.8641.8642.3532.6662.7262.7322.7292.7242.8422.8462.8472.8492.852.852.8512.852.8532.8542.882.6482.6512.2251.140.951
Percentage of NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable us-gaap:ConsolidatedEntities

srt:Subsidiaries


Noncontrolling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value1.8231.8461.8641.8642.3532.6662.7262.7322.7292.7242.8422.8462.8472.849
Percentage of NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance us-gaap:ConsolidatedEntities

us-gaap:NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance

srt:PartnershipInterest


Noncontrolling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value3.9874.4834.0422.3631.9333.68
Percentage of NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance100.0100.0100.0100.0100.0100.0

us-gaap:OperatingLeaseCost

us-gaap:OperatingLeaseCost


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value6.7076.7396.8726.9737.8317.3678.2978.2958.2988.2986.3049.5078.8468.308
Percentage of OperatingLeaseCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingLeaseCost us-gaap:ConsolidatedEntities

srt:Subsidiaries


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value6.7076.7396.8726.9737.8317.3678.2978.2958.2988.2986.3049.5078.8468.308
Percentage of OperatingLeaseCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingLeaseCost us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Operating
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-30
Value6.3856.2016.3616.7136.2345.9014.397
Percentage of OperatingLeaseCost91.679.286.380.975.171.146.3

us-gaap:OperatingLeaseCost us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

slg:OneVanderbilt


Operating
Period End2021-06-302021-03-31
Value0.70.1
Percentage of OperatingLeaseCost10.41.5

us-gaap:OperatingLeaseExpense us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:OperatingLeaseExpense

us-gaap:CorporateJointVenture


Operating
Period End2021-06-302021-03-312020-06-302020-03-31
Value5.6435.6446.2016.361
Percentage of OperatingLeaseExpense100.0100.0100.0100.0

us-gaap:OperatingLeaseLeaseIncome

us-gaap:OperatingLeaseLeaseIncome


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value184188190195195222250248243238247250236239
Percentage of OperatingLeaseLeaseIncome100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingLeaseLeaseIncome us-gaap:ConsolidatedEntities

srt:Subsidiaries


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value184188190195195222250248244240247250
Percentage of OperatingLeaseLeaseIncome100.0100.0100.0100.0100.0100.0100.0100.0100.5100.5100.0100.0

us-gaap:OperatingLeaseLeaseIncomeLeasePayments

us-gaap:OperatingLeaseLeaseIncomeLeasePayments


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value165164163171172194217214215211215220209213
Percentage of OperatingLeaseLeaseIncomeLeasePayments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingLeaseVariableLeaseIncome

us-gaap:OperatingLeaseVariableLeaseIncome


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value2025252121273132282731292726
Percentage of OperatingLeaseVariableLeaseIncome100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-54.183422.678-0.124-6.172-53.74310-12.043-23.423-18.105-20.4024.1784.2629.658
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax us-gaap:RelatedPartyTransactionsByRelatedParty, us-gaap:StatementEquityComponents

us-gaap:CorporateJointVenture, us-gaap:AccumulatedGainLossCashFlowHedgeIncludingNoncontrollingInterest


Other
Period End2021-06-302021-03-312020-12-312020-09-30
Value-52.344330.381-0.19
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax96.677.614.2153.2

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedGainLossCashFlowHedgeIncludingNoncontrollingInterest


Other
Period End2021-06-302021-03-312020-12-312020-09-30
Value-2.3179.7711.506-0.303
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax4.323.056.2244.4

us-gaap:AccumulatedNetInvestmentGainLossIncludingPortionAttributableToNoncontrollingInterest


Other
Period End2021-06-302021-03-312020-12-312020-09-30
Value0.478-0.2470.7910.369
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax-0.9-0.629.5-297.6

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value-57.918451.962-0.517-8.494-52.17110-12.606-25.033-17.332-23.3454.47
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax us-gaap:DerivativeInstrumentRisk

us-gaap:InterestRateSwap


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-30
Value-2.46510-0.318-7.407-45.082-10.169-20.876-11.9632.207
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax4.322.661.587.286.480.783.469.049.4

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value-55.453340.398-0.199-1.087-7.0891.641-2.437-4.157-5.369-8.4562.263
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax95.777.420.338.512.813.615.319.316.631.036.250.6

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value-2841000.02655000.0365000.0317000.0-95000.0-2886000.0593000.0-607000.0-1258000.0-1003000.0-1141000.0210000.0245000.0619000.0209000.0-4000.0-100000.0-199000.01556000.0118000.0-53000.0-322000.0282000.0-191000.042000.0-200000.0-172000.0113000.0276000.0-42000.0121000.0-25000.0456000.059000.08000.0-59000.0-153000.0-184000.0-118000.0-67000.0
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest us-gaap:ConsolidatedEntities

srt:PartnershipInterest


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value-2841000.02655000.0365000.0317000.0-95000.0-2886000.0
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0

srt:Subsidiaries


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-2841000.02655000.0365000.0317000.0-95000.0-2886000.0593000.0-607000.0-1258000.0-1003000.0-1141000.0210000.0245000.0619000.0
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value-47.966486.171-1.503-52.383-11.737-24.39-19.1133.6774.0499.9694.419-0.169-2.157-5.626362.4840.664-8.4737.072-4.9150.904-4.83-4.0843.38.6760.3394.038-0.6277.4953.47
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value-47.966486.171-1.503-52.383-11.737-24.39-19.1133.6774.0499.9694.419-0.169-2.157-5.626362.4840.664-8.4737.072-4.9150.904-4.83-4.0843.38.6760.3394.038-0.6277.4953.47
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value0.506-0.2580.3891.992-4.5340.230.5720.768-0.0320.318-0.3250.00.0440.263-4.750.0-0.030.354-1.223-0.270.317-1.3040.65-3.519-0.5061.6590.1291.1910.513-1.8481.641-3.06-0.825-0.5420.77-4.7251.528-5.7196.08
Percentage of OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax us-gaap:ConsolidatedEntities

srt:Subsidiaries


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0.506-0.2580.3891.992-4.5340.230.5720.768-0.0320.318-0.325
Percentage of OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherNoncashIncomeExpense

us-gaap:OtherNoncashIncomeExpense


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value-2.573-15.564-0.304-7.226-6.538-1.11-9.844154.111-9.5425.9750.4972.751-12.1551.227-0.8723.165-20.716-4.645-8.718149144.531128.182-4.59151.959-1.63126.0353.4336.2622162.0411.795-5.5540.7730.616-5.5971.823-11.8580.756
Percentage of OtherNoncashIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherNoncashIncomeExpense us-gaap:ConsolidatedEntities

srt:Subsidiaries


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-2.573-15.564-0.304-7.226-6.538-1.11-9.844154.111-9.5425.9750.4972.751-12.155
Percentage of OtherNoncashIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PartnersCapitalAccountDistributions us-gaap:ConsolidatedEntities

us-gaap:PartnersCapitalAccountDistributions

srt:Subsidiaries


Partners
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value6263646622696970696972
Percentage of PartnersCapitalAccountDistributions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PartnersCapitalAccountDistributions us-gaap:ConsolidatedEntities, us-gaap:PartnerCapitalComponents, us-gaap:StatementEquityComponents

srt:Subsidiaries, us-gaap:GeneralPartner, us-gaap:CommonStock


Partners
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value6263646622696970696972
Percentage of PartnersCapitalAccountDistributions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PartnersCapitalAccountRedemptions

us-gaap:PartnersCapitalAccountRedemptions


Partners
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value0.00.08.660.0840.00.0250.00.446140.01.560.06.2222.110.1313190.9514.6427.153143.6130.585375.2613.3266.483160.00.00.01770160.2080.2750.00.140.00.7250.0
Percentage of PartnersCapitalAccountRedemptions0.00.0100.0100.00.0100.00.0100.0100.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.0100.0100.0100.0100.0100.00.0100.00.0100.00.0

us-gaap:PartnersCapitalAccountRedemptions us-gaap:ConsolidatedEntities

srt:Subsidiaries


Partners
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.00.08.660.0840.00.0250.00.446140.01.560.0
Percentage of PartnersCapitalAccountRedemptions0.00.0100.0100.00.0100.00.0100.0100.00.0100.00.0

us-gaap:PaymentsForRepurchaseOfRedeemablePreferredStock

us-gaap:PaymentsForRepurchaseOfRedeemablePreferredStock


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302012-12-31
Value0.03.6310.02240193.00.00.0150.8580.00.20.150.150.00.1250.00.30.152.4090.440.00.00.00.22.00.00.00.00.0330.00.0
Percentage of PaymentsForRepurchaseOfRedeemablePreferredStock0.0100.00.0100.0100.0100.0100.00.00.0100.0100.00.0100.0100.0100.00.0100.00.0100.0100.0100.0100.00.00.00.0100.0100.00.00.00.0100.00.00.0

us-gaap:PaymentsForRepurchaseOfRedeemablePreferredStock us-gaap:ConsolidatedEntities

srt:Subsidiaries


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.03.6310.02240193.00.00.0150.8580.00.20.15
Percentage of PaymentsForRepurchaseOfRedeemablePreferredStock0.0100.00.0100.0100.0100.0100.00.00.0100.0100.00.0100.0100.0

us-gaap:PaymentsRelatedToTaxWithholdingForShareBasedCompensation

us-gaap:PaymentsRelatedToTaxWithholdingForShareBasedCompensation


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value54000.02788000.00004752000.0369000.0003126000.03858000.0-3858000.003842000.00063000.03816000.0
Percentage of PaymentsRelatedToTaxWithholdingForShareBasedCompensation100.0100.00.00.00.0100.0100.00.00.0100.0100.0100.00.0100.00.00.0100.0100.0

us-gaap:PaymentsRelatedToTaxWithholdingForShareBasedCompensation us-gaap:ConsolidatedEntities

srt:Subsidiaries


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value54000.02788000.00004752000.0369000.0003126000.00003842000.0
Percentage of PaymentsRelatedToTaxWithholdingForShareBasedCompensation100.0100.00.00.00.0100.0100.00.00.0100.00.0-0.00.0100.0

us-gaap:PaymentsToAcquireCommercialRealEstate

us-gaap:PaymentsToAcquireCommercialRealEstate


Payments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.00.00.0860.995-0.7472620.0
Percentage of PaymentsToAcquireCommercialRealEstate0.00.00.0100.0100.0100.0100.00.0

us-gaap:PaymentsToAcquireCommercialRealEstate us-gaap:ConsolidatedEntities

srt:Subsidiaries


Payments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.00.00.0860.995-0.7472620.0
Percentage of PaymentsToAcquireCommercialRealEstate0.00.00.0100.0100.0100.0100.00.0

us-gaap:PaymentsToAcquireEquityMethodInvestments

us-gaap:PaymentsToAcquireEquityMethodInvestments


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value172130219.4128.90614162473101442035127619858.01544186.60333182583164461511830383149552726105143529314.4891.452801.084
Percentage of PaymentsToAcquireEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsToAcquireEquityMethodInvestments us-gaap:ConsolidatedEntities

srt:Subsidiaries


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value172130219.4128.906141624731014420351
Percentage of PaymentsToAcquireEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsToMinorityShareholders

us-gaap:PaymentsToMinorityShareholders


Payments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-30
Value0.00.00.01.5360.0540.0
Percentage of PaymentsToMinorityShareholders0.00.00.0100.0100.00.0

us-gaap:PaymentsToMinorityShareholders us-gaap:ConsolidatedEntities

srt:Subsidiaries


Payments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-30
Value0.00.00.01.5360.0540.0
Percentage of PaymentsToMinorityShareholders0.00.00.0100.0100.00.0

us-gaap:PreferredStockDividendsAndOtherAdjustments us-gaap:ConsolidatedEntities

us-gaap:PreferredStockDividendsAndOtherAdjustments

srt:Subsidiaries


Preferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value3.7373.7383.7383.7373.7383.7373.7383.7373.7383.7373.7383.7373.7383.7373.7383.7373.738
Percentage of PreferredStockDividendsAndOtherAdjustments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PreferredStockDividendsPerShareCashPaid us-gaap:ConsolidatedEntities, us-gaap:StatementClassOfStock

us-gaap:PreferredStockDividendsPerShareCashPaid

srt:Subsidiaries, slg:SeriesKPreferredStock


Preferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value00.875000.8750000.875
Percentage of PreferredStockDividendsPerShareCashPaid0.0100.00.00.0100.00.00.00.0100.0

srt:Subsidiaries, slg:SeriesLPreferredStock


Preferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value01.0001.00001.0
Percentage of PreferredStockDividendsPerShareCashPaid0.0114.30.00.0114.30.00.00.0114.3

srt:Subsidiaries, slg:SeriesMPreferredStock


Preferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value00.9375000.93750000.9375
Percentage of PreferredStockDividendsPerShareCashPaid0.0107.10.00.0107.10.00.00.0107.1

srt:Subsidiaries, slg:SeriesPPreferredStock


Preferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value01.0001.00001.0
Percentage of PreferredStockDividendsPerShareCashPaid0.0114.30.00.0114.30.00.00.0114.3

srt:Subsidiaries, slg:SeriesQPreferredStock


Preferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value00.875000.8750000.875
Percentage of PreferredStockDividendsPerShareCashPaid0.0100.00.00.0100.00.00.00.0100.0

srt:Subsidiaries, slg:SeriesRPreferredStock


Preferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value00.875000.8750000.875
Percentage of PreferredStockDividendsPerShareCashPaid0.0100.00.00.0100.00.00.00.0100.0

srt:Subsidiaries, slg:SeriesSPreferredStock


Preferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value01.0001.00001.0
Percentage of PreferredStockDividendsPerShareCashPaid0.0114.30.00.0114.30.00.00.0114.3

srt:Subsidiaries, slg:SeriesVPreferredStock


Preferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-30
Value00.875000.87500
Percentage of PreferredStockDividendsPerShareCashPaid0.0100.00.00.0100.00.00.0

srt:Subsidiaries, us-gaap:SeriesAPreferredStock


Preferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value035.00035.000035.0
Percentage of PreferredStockDividendsPerShareCashPaid0.04000.00.00.04000.00.00.00.04000.0

srt:Subsidiaries, us-gaap:SeriesFPreferredStock


Preferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value070.00070.000070.0
Percentage of PreferredStockDividendsPerShareCashPaid0.08000.00.00.08000.00.00.00.08000.0

srt:Subsidiaries, us-gaap:SeriesGPreferredStock


Preferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value01.125001.1250001.125
Percentage of PreferredStockDividendsPerShareCashPaid0.0128.60.00.0128.60.00.00.0128.6

us-gaap:ProceedsFromIssuanceOfCommonStock us-gaap:StatementClassOfStock

us-gaap:ProceedsFromIssuanceOfCommonStock

slg:DividendReinvestmentAndStockPurchasePlan


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302015-12-312015-09-302015-06-302015-03-312013-06-302013-03-312012-06-302012-03-31
Value0.1160.3510.440.2020.1980.1660.0310.0390.2160.0470.0720.0520.0220.0420.0380.0740.0550.00.0990.0130.0130.099
Percentage of ProceedsFromIssuanceOfCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.00.0100.0

us-gaap:ProceedsFromIssuanceOfSecuredDebt

us-gaap:ProceedsFromIssuanceOfSecuredDebt


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value9.38110534865411015327131710922512811199900.0081.1977781525.6932222714315991060.015040014801212760.00.09801160.010051088650650401.46862
Percentage of ProceedsFromIssuanceOfSecuredDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.00.00.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromIssuanceOfSecuredDebt us-gaap:ConsolidatedEntities

srt:Subsidiaries


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value9.38110534865411015327131710922512811199
Percentage of ProceedsFromIssuanceOfSecuredDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromOtherDebt

us-gaap:ProceedsFromOtherDebt


Proceeds
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value405300.01501125150420520730102045537579527765560180520385107539066577145380603320474215155938345168300500675266458367530.0250
Percentage of ProceedsFromOtherDebt100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0

us-gaap:ProceedsFromOtherDebt us-gaap:ConsolidatedEntities

srt:Subsidiaries


Proceeds
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value405300.015011251504205207301020455
Percentage of ProceedsFromOtherDebt100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromRealEstateAndRealEstateJointVentures

us-gaap:ProceedsFromRealEstateAndRealEstateJointVentures


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value335627798315891690.4221241433813235040952293203.04950317761391445806.058485463991481098.9142120.05.852108443.011230.09.655
Percentage of ProceedsFromRealEstateAndRealEstateJointVentures100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.00.0100.0

us-gaap:ProceedsFromRealEstateAndRealEstateJointVentures us-gaap:ConsolidatedEntities

srt:Subsidiaries


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value335627798315891690.42212414338132350409
Percentage of ProceedsFromRealEstateAndRealEstateJointVentures100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromSaleAndMaturityOfMarketableSecurities

us-gaap:ProceedsFromSaleAndMaturityOfMarketableSecurities


Proceeds
Period End2021-06-302021-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302012-12-31
Value0.04.5280.00.00.00.00.00.7660.0540.0971.6885.180.00.9940.1370.1620.1334.5790.1143.5550.02.37-0.199.037
Percentage of ProceedsFromSaleAndMaturityOfMarketableSecurities0.0100.00.00.00.00.00.0100.00.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0

us-gaap:ProceedsFromSaleAndMaturityOfMarketableSecurities us-gaap:ConsolidatedEntities

srt:Subsidiaries


Proceeds
Period End2021-06-302021-03-31
Value0.04.528
Percentage of ProceedsFromSaleAndMaturityOfMarketableSecurities0.0100.0

us-gaap:ProceedsFromSaleOfAvailableForSaleSecuritiesDebt

us-gaap:ProceedsFromSaleOfAvailableForSaleSecuritiesDebt


Proceeds
Period End2021-06-302021-03-31
Value05000000.0
Percentage of ProceedsFromSaleOfAvailableForSaleSecuritiesDebt0.0100.0

us-gaap:ProceedsFromStockOptionsExercised

us-gaap:ProceedsFromStockOptionsExercised


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.1160.3510.440.2020.1980.1660.0320.0390.2160.047139.9884.930.771110.7692.8988.8082.7057.9733.1751.2563.5181.0921.4671094.7260.772108.9922.5191.4574.4494.5460.2967.2523.1061021.9331.1813.2953.8020.290.2561.82512
Percentage of ProceedsFromStockOptionsExercised100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromStockOptionsExercised us-gaap:ConsolidatedEntities

srt:Subsidiaries


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.1160.3510.440.2020.1980.1660.0320.0390.2160.047139.9884.930.771
Percentage of ProceedsFromStockOptionsExercised100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProvisionForLoanAndLeaseLosses

us-gaap:ProvisionForLoanAndLeaseLosses


Provision
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312013-12-312013-09-302012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value8.288.9576.813110.00.00.00.05.7391.0870.00.00.00.00.00.00.00.00.00.00.00.5648.5920.01.28-3.158.1781.3384.985
Percentage of ProvisionForLoanAndLeaseLosses100.0100.0100.0100.00.00.00.00.0100.0100.00.00.00.00.00.00.00.00.00.00.00.0100.0100.00.0100.0100.0100.0100.0100.0

us-gaap:ProvisionForLoanAndLeaseLosses us-gaap:ConsolidatedEntities

srt:Subsidiaries


Provision
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value8.288.9576.813110.00.00.00.05.7521.087
Percentage of ProvisionForLoanAndLeaseLosses100.0100.0100.0100.00.00.00.00.0100.2100.0

us-gaap:ProvisionForLoanLeaseAndOtherLosses

us-gaap:ProvisionForLoanLeaseAndOtherLosses


Provision
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value8.288.9576.813110.00.00.00.05.7520.00.00.00.00.00.00.00.00.00.00.00.03.08.375
Percentage of ProvisionForLoanLeaseAndOtherLosses100.0100.0100.0100.00.00.00.00.0100.00.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0

us-gaap:ProvisionForLoanLeaseAndOtherLosses us-gaap:ConsolidatedEntities

srt:Subsidiaries


Provision
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value8.288.9576.813110.00.00.00.05.752
Percentage of ProvisionForLoanLeaseAndOtherLosses100.0100.0100.0100.00.00.00.00.0100.0

us-gaap:ProvisionForLoanLossesExpensed

us-gaap:ProvisionForLoanLossesExpensed


Provision
Period End2021-03-312020-12-312020-09-302020-06-302020-03-31
Value0.0140.03.42.8
Percentage of ProvisionForLoanLossesExpensed0.0100.00.0100.0100.0

us-gaap:ProvisionForLoanLossesExpensed us-gaap:CumulativeEffectPeriodOfAdoption

srt:CumulativeEffectPeriodOfAdoptionAdjustment


Provision
Period End2020-12-31
Value14
Percentage of ProvisionForLoanLossesExpensed101.4

us-gaap:RealEstateTaxExpense

us-gaap:RealEstateTaxExpense


Real
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value43454443414647494646464845455864606160646261596156555855535557555253525352514544434038353736
Percentage of RealEstateTaxExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RealEstateTaxExpense us-gaap:ConsolidatedEntities

srt:Subsidiaries


Real
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value4345444341464749464646484545
Percentage of RealEstateTaxExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RealEstateTaxExpense us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CorporateJointVenture


Real
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value545459565153525351545756555735373534
Percentage of RealEstateTaxExpense123.4120.2132.7129.7124.2114.5110.6107.4111.3116.2123.2116.3123.2124.960.858.157.757.2

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax


Reclassification
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-6.217-5.802-6.275-6.295-4.669-1.36-1.571-0.3060.9671.0080.7890.5010.213-0.311
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax us-gaap:RelatedPartyTransactionsByRelatedParty, us-gaap:StatementEquityComponents

us-gaap:CorporateJointVenture, us-gaap:AccumulatedGainLossCashFlowHedgeIncludingNoncontrollingInterest


Reclassification
Period End2021-06-302021-03-312020-12-312020-09-30
Value-1.935-1.606-1.498-1.383
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax31.127.723.922.0

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedGainLossCashFlowHedgeIncludingNoncontrollingInterest


Reclassification
Period End2021-06-302021-03-312020-12-312020-09-30
Value-4.282-4.196-4.777-4.912
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax68.972.376.178.0

us-gaap:RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty

slg:AllianceBuildingServices


Related
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value3.32.33.02.83.95.65.62.94.85.05.14.06.65.75.84.57.35.37.13.87.05.74.64.06.85.94.73.56.34.84.24.15.04.74.73.55.24.33.53.14.63.43.1
Percentage of RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty100.0