NFG


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

Table of contents



us-gaap:CommonStockValue
us-gaap:StatementEquityComponents
us-gaap:CommonStockSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareDiluted
us-gaap:StatementEquityComponents
us-gaap:AllocatedShareBasedCompensationExpense

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest

us-gaap:CostOfGoodsAndServicesSold
us-gaap:ProductOrService, us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:CostsAndExpenses

us-gaap:GainsLossesOnExtinguishmentOfDebt
us-gaap:LongtermDebtType

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:IncomeTaxExpenseBenefit
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:InterestExpenseLongTermDebt

us-gaap:NetIncomeLoss
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome
us-gaap:StatementBusinessSegments
us-gaap:StatementEquityComponents

us-gaap:OperatingIncomeLoss

us-gaap:OtherComprehensiveIncomeLossNetOfTax
us-gaap:StatementEquityComponents

us-gaap:OtherNonoperatingIncomeExpense

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments

us-gaap:Revenues
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents
us-gaap:InvestmentType, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents
us-gaap:StatementBusinessSegments

us-gaap:Assets
us-gaap:StatementBusinessSegments

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:AssetsCurrent

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:InventoryRawMaterialsAndSupplies

us-gaap:OtherAssetsCurrent

us-gaap:PropertyPlantAndEquipmentGross

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:DeferredTaxAssetsLiabilitiesNet
us-gaap:BalanceSheetLocation
us-gaap:OperatingLeaseRightOfUseAsset

us-gaap:OtherAssetsNoncurrent
us-gaap:InvestmentType
us-gaap:EquitySecuritiesFvNi

us-gaap:AccountsPayableCurrent
us-gaap:IncomeTaxAuthority
us-gaap:AccruedIncomeTaxesCurrent

us-gaap:AccruedLiabilitiesCurrent

us-gaap:DividendsPayableCurrent

us-gaap:LiabilitiesCurrent

us-gaap:LongTermDebtCurrent
us-gaap:LongtermDebtType
us-gaap:BalanceSheetLocation
us-gaap:OperatingLeaseLiabilityCurrent
us-gaap:StatementBusinessSegments
us-gaap:OtherAccruedLiabilitiesCurrent

us-gaap:LiabilitiesNoncurrent

us-gaap:LongTermDebt

us-gaap:LongTermDebtNoncurrent

us-gaap:DeferredIncomeTaxLiabilitiesNet
us-gaap:RetirementPlanType
us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent
us-gaap:BalanceSheetLocation
us-gaap:OperatingLeaseLiabilityNoncurrent

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive
us-gaap:BalanceSheetLocation
us-gaap:OperatingLeaseLiability

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

us-gaap:CommonStockValue

us-gaap:AdditionalPaidInCapital
us-gaap:StatementEquityComponents

us-gaap:RetainedEarningsAccumulatedDeficit
us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax
us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents
us-gaap:StockIssuedDuringPeriodValueNewIssues

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities
us-gaap:ImpairedLongLivedAssetsHeldAndUsedByType
us-gaap:DeferredIncomeTaxExpenseBenefit

us-gaap:DepreciationDepletionAndAmortization

us-gaap:IncreaseDecreaseInInventories

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetIncomeLoss
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome
us-gaap:StatementBusinessSegments
us-gaap:StatementEquityComponents

us-gaap:ShareBasedCompensation

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:ProceedsFromIssuanceOfLongTermDebt
us-gaap:LongtermDebtType

us-gaap:RepaymentsOfLongTermDebt

us-gaap:PaymentsOfDividendsCommonStock
us-gaap:LongtermDebtType
us-gaap:DebtInstrumentInterestRateStatedPercentage

us-gaap:DeferredTaxLiabilities

us-gaap:DeferredTaxAssetsNet

us-gaap:DeferredTaxAssetsValuationAllowance

us-gaap:ProceedsFromRepaymentsOfShortTermDebt

dei:EntityListingParValuePerShare

nfg:AcquisitionOfUpstreamAssetsAndMidstreamGatheringAssets
us-gaap:StatementBusinessSegments
nfg:AlternativeRevenuePrograms

nfg:BeginningRetainedEarningsUnappropriatedAndCurrentPeriodNetIncomeLoss

nfg:CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonthsAfterTax

nfg:CumulativeEffectofAdoptionofAuthoritativeGuidanceforHedging
us-gaap:StatementEquityComponents

nfg:ImpairmentOfOilAndGasProducingPropertiesAfterTax

nfg:ImpairmentofOilandGasProducingProperties

nfg:IncreaseDecreaseInCustomerAdvancesCurrent
us-gaap:RetirementPlanType
nfg:NetAmortizationAndDeferralForRegulatoryPurposesIncludingVolumetricAdjustments

nfg:NetProceedsFromSaleOfTimberProperties

nfg:OtherComprehensiveIncomeLossCumulativeEffectofAdoptionofAuthoritativeGuidanceforHedging

nfg:OtherComprehensiveIncomeLossCumulativeEffectofAdoptionofAuthoritativeGuidanceforHedgingTax
us-gaap:StatementGeographical
nfg:ProposedRefundToCustomersFromOverCollectionOfOPEBExpenses

us-gaap:AccountsReceivablePurchase

us-gaap:AllowanceForDoubtfulAccountsReceivableWriteOffs

us-gaap:CapitalExpendituresIncurredButNotYetPaid

us-gaap:CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortization

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect

us-gaap:CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths

us-gaap:CommonStockDividendsPerShareDeclared

us-gaap:DeferredIncomeTaxesAndTaxCredits
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanContributionsByEmployer
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanInterestCost
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanServiceCost
us-gaap:StatementBusinessSegments
us-gaap:DerivativeGainLossOnDerivativeNet

us-gaap:DividendsCommonStockCash
us-gaap:StatementEquityComponents

us-gaap:EffectOnFutureCashFlowsAmount

us-gaap:GainLossOnSaleOfTimberProperty

us-gaap:IncreaseDecreaseInAccountsPayableTrade

us-gaap:IncreaseDecreaseInAccruedLiabilities

us-gaap:IncreaseDecreaseInDeferredGasCost

us-gaap:IncreaseDecreaseInOtherCurrentAssets

us-gaap:IncreaseDecreaseInOtherNoncurrentAssets

us-gaap:IncreaseDecreaseInOtherOperatingLiabilities

us-gaap:IncreaseDecreaseInReceivables

us-gaap:IncreaseDecreaseInRegulatoryClauseRevenue

us-gaap:IncreaseDecreaseInSecurityDeposits

us-gaap:InterestExpenseOther

us-gaap:LeaseCost

us-gaap:OperatingLeaseCost

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax
us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossBeforeTax

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax
us-gaap:DerivativeInstrumentRisk, us-gaap:IncomeStatementLocation
us-gaap:IncomeStatementLocation, us-gaap:InvestmentType

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax
us-gaap:DerivativeInstrumentRisk, us-gaap:IncomeStatementLocation
us-gaap:IncomeStatementLocation, us-gaap:InvestmentType

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax

us-gaap:OtherComprehensiveIncomeLossTax

us-gaap:OtherNoncashIncomeExpense

us-gaap:PaymentsForProceedsFromOtherInvestingActivities

us-gaap:PaymentsForRepurchaseOfEquity

us-gaap:ProceedsFromIssuanceOrSaleOfEquity

us-gaap:ProvisionForDoubtfulAccounts
us-gaap:StatementGeographical
us-gaap:PublicUtilitiesRequestedRateIncreaseDecreaseAmount

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax
us-gaap:StatementEquityComponents
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue

us-gaap:ShortTermLeaseCost
us-gaap:PropertyPlantAndEquipmentByType
us-gaap:StatementEquityComponents
us-gaap:StockIssuedDuringPeriodSharesNewIssues
us-gaap:StatementEquityComponents
us-gaap:StockIssuedDuringPeriodSharesOther
us-gaap:StatementEquityComponents
us-gaap:StockIssuedDuringPeriodValueOther
us-gaap:StatementEquityComponents
us-gaap:StockRepurchasedDuringPeriodValue

us-gaap:SubleaseIncome

us-gaap:TaxesExcludingIncomeAndExciseTaxes
us-gaap:StatementBusinessSegments
us-gaap:UtilitiesOperatingExpenseMaintenanceAndOperations

us-gaap:VariableLeaseCost

dei:EntityCommonStockSharesOutstanding

nfg:AcceleratedAMTCreditRefundReceivedUnderCARESAct

nfg:AnticipatedProceedsFromSaleOfCertainTimberAndOtherAssets

nfg:AssetAcquisitionAssets
us-gaap:StatementBusinessSegments

nfg:AssetAcquisitionConsiderationTransferred

nfg:AssetAcquisitionInventory
us-gaap:StatementBusinessSegments

nfg:AssetAcquisitionTransactionCosts

nfg:CommittedCreditFacilityDebtToCapitalizationRatioCeilingTestImpairmentAdjustmentAmount

nfg:CommittedCreditFacilityDebttoCapitalizationRatioCeilingTestImpairmentAdjustment

nfg:CommittedCreditFacilityDebttoCapitalizationRatioCeilingTestImpairmentMaximumAdjustment

nfg:CostOfRemovalRegulatoryLiability
nfg:CreditRiskExposure, us-gaap:DerivativeInstrumentRisk
nfg:CreditRiskExposurePerCounterparty
us-gaap:DerivativeInstrumentRisk

nfg:CustomerAdvances

nfg:DeferredTaxAssetsPensionAndOtherPostRetirementCosts

nfg:DeferredTaxLiabilitiesPensionAndOtherPostRetirementCosts
us-gaap:RetirementPlanTaxStatus
nfg:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityBeforeTax
us-gaap:RetirementPlanType
us-gaap:RetirementPlanTaxStatus
nfg:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityNetGainsLossesBeforeTax
us-gaap:RetirementPlanType
us-gaap:RetirementPlanType
nfg:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityNetPriorServiceCostCreditBeforeTax

nfg:DepreciablePlantAssets
us-gaap:StatementBusinessSegments

nfg:EarningsReinvestedInBusinessAvailableForDividends

nfg:EmissionAllowances

nfg:FairValueAssetsLiabilitiesMeasuredOnRecurringBasisNet
us-gaap:FairValueByFairValueHierarchyLevel

nfg:FairValueAssetsMeasuredOnRecurringBasisTotal
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueConcentrationOfRiskDisclosureItems

nfg:FairValueLiabilitiesMeasuredOnRecurringBasisTotal
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueConcentrationOfRiskDisclosureItems

nfg:FirstInstallmentOfAMTCreditRefunds

nfg:FullCostCeilingExceedsBookValueOfOilAndGasProperties

nfg:InterestPayableOnLongTermDebt

nfg:LiabilityforRoyaltyandWorkingInterestCurrent

nfg:MaterialsAndSuppliesAtAverageCost
us-gaap:DerivativeInstrumentRisk
nfg:MaximumCreditRiskExposurePerCounterparty
us-gaap:LongtermDebtType
nfg:MediumTermNotesPayable
us-gaap:SubsequentEventType
nfg:NetAcresAcquiredInTiogaCounty

nfg:NetHedgingGainsLossesInAccumulatedOtherComprehensiveIncomeLoss

nfg:NetHedgingGainsLossesinAccumulatedOtherComprehensiveIncomeLoss
us-gaap:StatementGeographical
nfg:NoncurrentAssets1
us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship
nfg:NonmonetaryNotionalAmountOfPriceRiskCashFlowHedgeDerivativesCrudeOil
us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship
nfg:NonmonetaryNotionalAmountOfPriceRiskCashFlowHedgeDerivativesNaturalGas
us-gaap:LongtermDebtType
nfg:Notes

nfg:ProvedUndevelopedReservesAdditions

nfg:ProvedUndevelopedReservesConversionsToDevelopedReserves
us-gaap:StatementGeographical

nfg:ProvedUndevelopedReservesDecrease

nfg:ProvedUndevelopedReservesPercentage

nfg:ProvedUndevelopedReservesRemoved
us-gaap:StatementGeographical

nfg:ProvedUndevelopedReservesRevisions

nfg:ProvedUndevelopedReservesUpwardRevisions

nfg:PurchasePriceToAcquireUpstreamAssetsAndMidstreamGatheringAssets

nfg:RecoverableFutureTaxes
us-gaap:ValuationAllowanceByDeferredTaxAsset
us-gaap:AwardType
nfg:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisableWeightedAverageExercisePrice
us-gaap:AwardType
nfg:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpirationsInPeriodWeightedAverageExercisePrice
us-gaap:AwardType
nfg:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageExercisePrice

nfg:TaxesRefundableToCustomers
us-gaap:ValuationAllowanceByDeferredTaxAsset

nfg:TotalOtherAssets

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesCashInflows

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesDevelopmentCosts

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesIncomeTaxExpense

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesNetCashFlows

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesProductionCosts

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesTenPercentAnnualDiscountForEstimatedTimingOfCashFlows
us-gaap:Energy
srt:ProvedDevelopedAndUndevelopedReservesNet
us-gaap:Energy, us-gaap:StatementGeographical
us-gaap:Energy
srt:ProvedDevelopedReservesVolume
us-gaap:Energy, us-gaap:StatementGeographical

srt:ProvedUndevelopedReserveVolume
us-gaap:Energy
us-gaap:Energy, us-gaap:StatementGeographical
us-gaap:StatementGeographical

srt:StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves

us-gaap:AccountsAndOtherReceivablesNetCurrent
us-gaap:StatementBusinessSegments
us-gaap:AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax

us-gaap:AllowanceForDoubtfulAccountsReceivable

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent

us-gaap:AociLossCashFlowHedgeCumulativeGainLossAfterTax

us-gaap:AssetRetirementObligation

us-gaap:AssetRetirementObligationsNoncurrent

us-gaap:AssetsHeldForSaleNotPartOfDisposalGroup

us-gaap:CapitalizationLongtermDebtAndEquity

us-gaap:CapitalizedCostsAccumulatedDepreciationDepletionAmortizationAndValuationAllowanceForRelatingToOilAndGasProducingActivities

us-gaap:CapitalizedCostsAssetRetirementCosts

us-gaap:CapitalizedCostsOilAndGasProducingActivitiesGross

us-gaap:CapitalizedCostsOilAndGasProducingActivitiesNet

us-gaap:CapitalizedCostsProvedProperties

us-gaap:CapitalizedCostsUnprovedProperties

us-gaap:CashAndCashEquivalentsFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:CashSurrenderValueOfLifeInsurance

us-gaap:CommercialPaperAtCarryingValue
us-gaap:StatementEquityComponents
us-gaap:CommonStockValueOutstanding
us-gaap:StatementBusinessSegments
us-gaap:ContractualObligationDueAfterFifthYear
us-gaap:StatementBusinessSegments
us-gaap:ContractualObligationDueInFifthYear
us-gaap:StatementBusinessSegments
us-gaap:ContractualObligationDueInFourthYear
us-gaap:StatementBusinessSegments
us-gaap:ContractualObligationDueInNextTwelveMonths
us-gaap:StatementBusinessSegments
us-gaap:ContractualObligationDueInSecondYear
us-gaap:StatementBusinessSegments
us-gaap:ContractualObligationDueInThirdYear

us-gaap:CreditRiskDerivativeAssetsAtFairValue
nfg:CreditRiskExposure

us-gaap:CreditRiskDerivativeLiabilitiesAtFairValue
us-gaap:LongtermDebtType
us-gaap:DebtInstrumentCarryingAmount
us-gaap:LongtermDebtType
us-gaap:DebtInstrumentFaceAmount

us-gaap:DebtInstrumentFairValue

us-gaap:DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet

us-gaap:DebtInstrumentUnusedBorrowingCapacityAmount

us-gaap:DeferredCosts

us-gaap:DeferredCreditsAndOtherLiabilitiesNoncurrent

us-gaap:DeferredTaxAssetsCapitalLossCarryforwards

us-gaap:DeferredTaxAssetsCharitableContributionCarryforwards

us-gaap:DeferredTaxAssetsGross
us-gaap:IncomeTaxAuthority
us-gaap:DeferredTaxAssetsOperatingLossCarryforwardsNotSubjectToExpiration
us-gaap:IncomeTaxAuthority
us-gaap:DeferredTaxAssetsOperatingLossCarryforwardsSubjectToExpiration

us-gaap:DeferredTaxAssetsOther

us-gaap:DeferredTaxLiabilitiesOther

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment
us-gaap:RetirementPlanTaxStatus
us-gaap:DefinedBenefitPlanAccumulatedBenefitObligation
us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditAfterTax

us-gaap:DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent
us-gaap:RetirementPlanType
us-gaap:RetirementPlanTaxStatus
us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
us-gaap:RetirementPlanType
us-gaap:RetirementPlanTaxStatus
us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease
us-gaap:RetirementPlanType
us-gaap:BalanceSheetLocation, us-gaap:RetirementPlanTaxStatus
us-gaap:DefinedBenefitPlanBenefitObligation
us-gaap:RetirementPlanTaxStatus
us-gaap:RetirementPlanType
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo
us-gaap:Range, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear
us-gaap:Range, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureEmployerContributionsRemainderOfFiscalYear
us-gaap:RetirementPlanType
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanFundedStatusOfPlan
us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount
us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:RetirementPlanType
us-gaap:Range, us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanPlanAssetsTargetAllocationPercentage

us-gaap:DefinedBenefitPlanUltimateHealthCareCostTrendRate1
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:InvestmentType
us-gaap:DerivativeAssets
us-gaap:FairValueConcentrationOfRiskDisclosureItems, us-gaap:InvestmentType
us-gaap:InvestmentType

us-gaap:DerivativeInstrumentsAndHedgesLiabilities

us-gaap:DerivativeInstrumentsAndHedgesNoncurrent
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:InvestmentType
us-gaap:DerivativeLiabilities
us-gaap:FairValueConcentrationOfRiskDisclosureItems, us-gaap:InvestmentType
us-gaap:InvestmentType
us-gaap:InvestmentType
us-gaap:DerivativeNotionalAmount
us-gaap:AwardType
us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized

us-gaap:EnergyRelatedInventoryGasStoredUnderground
us-gaap:PublicUtilitiesInventory
us-gaap:StatementBusinessSegments
us-gaap:FairValueByAssetClass, us-gaap:RetirementPlanType
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
us-gaap:RetirementPlanType
us-gaap:IncomeTaxAuthority
us-gaap:IncomeTaxReceivable
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:InvestmentType
us-gaap:InvestmentsFairValueDisclosure
us-gaap:InvestmentType

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths
us-gaap:CreditFacility
us-gaap:LineOfCreditFacilityCurrentBorrowingCapacity
us-gaap:LongtermDebtType
us-gaap:CreditFacility
us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity
us-gaap:CreditFacility, us-gaap:SubsequentEventType

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo

us-gaap:LossContingencyEstimateOfPossibleLoss
us-gaap:EnvironmentalRemediationSite

us-gaap:MarginDepositAssets
us-gaap:DerivativeInstrumentRisk
us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:OperatingLeaseWeightedAverageDiscountRatePercent
us-gaap:StatementGeographical
us-gaap:OperatingLossCarryforwards

us-gaap:OtherInvestments

us-gaap:OtherPrepaidExpenseCurrent

us-gaap:PensionAndOtherPostretirementAndPostemploymentBenefitPlansLiabilitiesNoncurrent

us-gaap:PrepaidTaxes
us-gaap:RetirementPlanType
us-gaap:PrescriptionDrugSubsidyReceiptsAfterYearFive
us-gaap:RetirementPlanType
us-gaap:PrescriptionDrugSubsidyReceiptsNextTwelveMonths
us-gaap:RetirementPlanType
us-gaap:PrescriptionDrugSubsidyReceiptsYearFive1
us-gaap:RetirementPlanType
us-gaap:PrescriptionDrugSubsidyReceiptsYearFour1
us-gaap:RetirementPlanType
us-gaap:PrescriptionDrugSubsidyReceiptsYearThree1
us-gaap:RetirementPlanType
us-gaap:PrescriptionDrugSubsidyReceiptsYearTwo1

us-gaap:RecordedUnconditionalPurchaseObligationDueAfterFifthYear

us-gaap:RecordedUnconditionalPurchaseObligationDueInFifthYear

us-gaap:RecordedUnconditionalPurchaseObligationDueInFourthYear

us-gaap:RecordedUnconditionalPurchaseObligationDueInSecondYear

us-gaap:RecordedUnconditionalPurchaseObligationDueInThirdYear

us-gaap:RecordedUnconditionalPurchaseObligationDueWithinOneYear

us-gaap:RefundableGasCosts

us-gaap:RegulatoryAssets
us-gaap:RegulatoryAsset

us-gaap:RegulatoryAssetsCurrent
us-gaap:RegulatoryAsset

us-gaap:RegulatoryAssetsNoncurrent
us-gaap:RegulatoryAsset

us-gaap:RegulatoryLiabilities
us-gaap:RegulatoryLiability

us-gaap:RegulatoryLiabilityCurrent
us-gaap:RegulatoryLiability
us-gaap:StatementBusinessSegments

us-gaap:RegulatoryLiabilityNoncurrent
us-gaap:RegulatoryLiability

us-gaap:RevenueRemainingPerformanceObligation

us-gaap:SecurityDepositLiability
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant

us-gaap:ShortTermBankLoansAndNotesPayable

us-gaap:ShortTermBorrowings
us-gaap:IncomeTaxAuthority, us-gaap:TaxCreditCarryforward
us-gaap:TaxCreditCarryforwardAmount
us-gaap:StatementGeographical, us-gaap:TaxCreditCarryforward
us-gaap:TaxCreditCarryforward

us-gaap:UnamortizedLossReacquiredDebtNoncurrent

us-gaap:UnbilledReceivablesCurrent

us-gaap:UnrecoveredCostsForPurchasedGasAmount

us-gaap:UnsecuredDebt
us-gaap:ValuationAllowanceByDeferredTaxAsset
us-gaap:ValuationAllowancesAndReservesBalance
us-gaap:ValuationAllowancesAndReservesType

Plots across concepts


IncomeStatement
Other Comprehensive Income Loss Net Of Tax
Expenses
Other Nonoperating Income Expense
Balance Sheet
Goodwill
Assets
Cash And Cash Equivalents At Carrying Value
Current Assets
Other Assets Current
NonCurrent Assets
Other Assets Noncurrent
PropertyPlantAndEquipmentNet
Property Plant And Equipment Net
Liabilities
Liabilities Current
Current Liabilities
Accounts Payable Current
Noncurrent Liabilities
Deferred Income Tax Liabilities Net
Stockholders Equity
Accumulated Other Comprehensive Income Loss Net Of Tax
Per Share
Common Stock Dividends Per Share Declared
CashFlow
Net Cash Provided By Used In Investing Activities
NetCashProvidedByUsedInOperatingActivities
Share Based Compensation
NetCashProvidedByUsedInInvestingActivities
Net Cash Provided By Used In Investing Activities
NetCashProvidedByUsedInFinancingActivities
Net Cash Provided By Used In Financing Activities
Shares
Weighted Average Number Of Shares Outstanding Basic
LesseeOperatingLeaseLiabilityPaymentsDue
Lessee Operating Lease Liability Payments Due Year Four

Tables

  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
us-gaap:CommonStockValue █████▄▄▄▄▄▄▄▄▄▄▄▃▃▃▂▂▂▂▂▂▁▁▁▁91.17391.16491.15390.95590.94486.56286.55286.31586.30786.30186.27185.95785.94485.88285.76185.54385.46885.37585.29383.52283.48283.3383.2783.17483.03882.81382.782.54482.338
 us-gaap:CommonStockSharesOutstanding us-gaap:StatementEquityComponents us-gaap:CommonStock█████▂▂▂▂▂▂▂▁▁▁▁91.17391.16491.15390.95590.94486.56286.55286.31586.30786.30186.27185.95785.94485.88285.76185.543NANANANANA83.33NANANA82.813NANANA
us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding █▅▁91.76289891.64567991.508259NA88.32369986.56106686.883152NA86.83984186.76767386.708814NA86.50119486.32363686.325537NA86.06446486.00661485.79798984.15973484.00605NA83.67482383.67826183.699981NA83.78249383.67397783.420351
us-gaap:WeightedAverageNumberOfSharesOutstandingBasic ██▁91.17268391.16329191.007657NA87.96628986.56106686.37845NA86.30643486.29004786.032729NA85.93028985.80923385.630296NA85.42231385.33488785.18985183.49850883.390278NA83.22760283.10788482.870931NA82.68746782.40085182.223428
us-gaap:EarningsPerShareBasic ▆▆▅▁▅▂▆▅▅▆▆▅▅▆█▅▅▆▆▆▅▅▅▅▅▅▅▆▅0.951.230.85-1.60.47-1.231.00.550.741.051.190.440.731.072.320.530.71.051.041.030.810.590.520.810.730.450.571.40.71
us-gaap:EarningsPerShareDiluted ▆▆▅▁▅▂▆▅▅▆▆▅▅▆█▅▅▆▆▆▅▅▅▅▅▅▅▆▅0.941.230.85-1.60.47-1.231.00.540.731.041.180.440.731.062.30.530.691.041.041.020.810.580.520.810.730.450.561.380.7
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
 TTM Greenblatt ROC _ _▇█▇▁▆▄▇▆▆▇▇▆▆▇▇▆▆▇▇▇▇▆▆▇▆▅▆▇▆150.07214.039143.542-173.97980.397-24.58148.0283.94112.827153.359161.68380.629107.76156.702141.99587.395123.354169.957172.139162.991131.208107.26590.293132.097118.39475.19194.805153.756117.411
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
 us-gaap:AllocatedShareBasedCompensationExpense us-gaap:StatementEquityComponents us-gaap:AdditionalPaidInCapital▄▆▅▇▁▆▃▇███▅▅▅▅3.1964.2833.4964.7771.6993.8762.8284.6055.0545.0384.9173.6033.5583.5633.511NANANANANANANANANANANANANANA
us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest ▄▆▇▁▅▄▆▅▆▆▇▅▅▆█▆▆▇▅▆▆▅▆▆▆▆▆▆▅-49.99990.189112.79-218.50818.373-68.83582.59627.79285.37364.999141.7242.6438.38985.006187.85848.75760.501110.05239.68953.34182.32-2.27847.13368.63655.26664.75664.31487.7438.878
us-gaap:CostOfGoodsAndServicesSold ▂▅▃▁▂▅▄▁▃█18.737106.66151.62-5.77329.121118.2792.2724.72847.839195.037NANANANANANANANANANANANANANANANANANANA
us-gaap:CostsAndExpenses ▂▄▄▇▂█▃▁▂▅244.327337.076348.684461.968242.622515.675296.168209.401244.373399.185NANANANANANANANANANANANANANANANANANANA
us-gaap:GainsLossesOnExtinguishmentOfDebt 0.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:GainsLossesOnExtinguishmentOfDebt us-gaap:LongtermDebtType nfg:FourPointNinePercentNotesDueDecemberOneTwoThousandTwentyOne0.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest ▇█▇▁▆▄▇▆▇▇▇▆▇█▇▆▇██116.81152.646107.191-208.18254.384-69.222117.98658.69684.866120.38125.56954.32582.208130.116117.37761.06395.506142.255145.34NANANANANANANANANANA
us-gaap:IncomeTaxExpenseBenefit ▆▇▆▂▅▆▆▅▆▆▆▅▆▆▁▅▆▇▇▇▇▆▆▇▇▆▆█▆30.33540.2129.417-62.63713.13436.84631.39511.41521.11329.78522.90916.33119.18338.269-81.27715.48735.79252.97156.43255.18643.54938.72826.22844.87340.72523.17731.01772.13638.052
us-gaap:InterestExpenseLongTermDebt ▄█▄▄▃▃▃▃▃▃▃▃▃▃▃▄▄▄▄▂▂▂▂▂▁▁▁▁▂30.2248.8232.25632.15927.1425.2725.44325.59825.30325.27325.43928.53427.17727.14828.08729.2329.22528.91329.10322.78621.44821.40821.52920.42518.64117.57317.87617.92620.192
us-gaap:NetIncomeLoss ▆▆▆▁▅▂▆▅▅▆▆▅▅▆█▅▅▆▆▆▅▅▅▅▅▅▅▆▅86.475112.43677.774-145.54541.25-106.06886.59147.28263.75390.595102.6637.99563.02591.847198.65445.57759.71489.28488.90885.7267.94448.80243.18467.39260.69937.35646.891115.61158.543
us-gaap:OperatingIncomeLoss ▇█▇▁▆▄▇▆▆▇▇▆▆▇▇▆▆▇▇▇▇▆▆▇▆▅▆▇▆150.07214.039143.542-173.97980.397-24.58148.0283.94112.827153.359161.68380.629107.76156.702141.99587.395123.354169.957172.139162.991131.208107.26590.293132.097118.39475.19194.805153.756117.411
us-gaap:OtherComprehensiveIncomeLossNetOfTax ▁▆█▄▆█▆▆▇▅█▇▅▆▆▇▆▇▄▅▇▄▇▆▆█▇▅-136.474-22.24735.016-72.963-22.87737.233-3.995-19.48921.62-25.59639.064.646-24.636-6.841-10.7963.1810.78720.768-49.219-32.37914.376-51.083.9491.244-5.43327.39917.423-27.871NA
 us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents us-gaap:AccumulatedOtherComprehensiveIncome▁▆█▄▆█▆▆▇▅█▇▅▆▆-136.474-22.24735.016-72.963-22.87737.233-3.995-19.48921.62-25.59639.064.646-24.636-6.841-10.796NANANANANANANANANANANANANANA
us-gaap:OtherNonoperatingIncomeExpense ▆▃▆▇█▁▆█▇▅▄▇▆▃▆-2.028-10.875-2.1760.1572.547-17.48-3.041.435-1.456-5.919-9.602-0.969-3.612-13.092-3.503NANANANANANANANANANANANANANA
us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax ▃▆▄▁▂▅▄▁▂▆▅▁▂▆▃▁▂▅▄▇▄▂▂▆▄▁▃█▄394.397551.115441.16287.989323.019491.095444.188293.341357.2552.544499.597289.196342.912540.905419.655286.937348.368522.075422.5597.826452.854313.26328.861552.309432.423286.034380.979660.881450.948
us-gaap:Revenues ▃▆▄▁▂▅▄▁▂▆▅▁▂▆▃▁▂▅▄▇▄▂▂▆▄▁▃█▄394.397551.115441.16287.989323.019491.095444.188293.341357.2552.544490.247289.196342.912540.905419.655286.937348.368522.075422.5597.826452.854313.26328.861552.309432.423286.034380.979660.881450.948
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
us-gaap:Assets ██▇▇█▆▆▆▅▅▅▄▄▄▄▅▄▄▃▅▅▄▄▄▃▂▁▂▁7208.6757115.6527039.1686964.9357118.9856708.6596702.6586462.1576336.2476278.9756186.9286036.4865974.1035914.5735791.9326103.325867.5075804.6755661.7176274.6896108.1975935.1425836.8535835.4965747.7555284.7425133.2655183.3174981.981
us-gaap:LiabilitiesAndStockholdersEquity ██▇▇█▆▆▆▅▅▅▄▄▄▄▅▄▄▃▅▅▄▄▄▃▂▁▂▁7208.6757115.6527039.1686964.9357118.9856708.6596702.6586462.1576336.2476278.9756186.9286036.4865974.1035914.5735791.9326103.325867.5075804.6755661.7176274.6896108.1975935.1425836.8535835.4965747.7555284.7425133.2655183.3174981.981
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
us-gaap:AssetsCurrent ▃▃▃▁█▃▃▂▂▄▄▄▅▅▄█▄▄▃▃▂▂▂▄▅▂▄▅▄439.557457.184453.439314.198831.708496.27430.696362.623403.296506.297522.841544.591588.998592.993521.552818.28542.18556.946467.715489.95394.369355.576388.365516.415589.113385.312520.788620.115525.609
us-gaap:CashAndCashEquivalentsAtCarryingValue ▂▂▂▁█▂▁▁▂▂▂▄▅▄▃█▄▄▃▂▂▂▃▃▄▂▃▃▂118.01280.467109.41320.541556.264111.65534.96620.42887.515100.643109.754229.606313.307227.994166.289555.53285.325231.173136.493112.41361.01774.494140.815192.243224.26280.428184.71144.76779.622
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents ▂▂▂▁█▂▁▁▂▂▂▄▅▄▃█119.72280.467109.41320.541563.963122.38344.63227.2694.35102.626112.538233.047315.59231.651170.754557.271NANANANANANANANANANANANANA
us-gaap:InventoryRawMaterialsAndSupplies ██▇█▇▇▄▅▄▄▃▃▃▃▃▃▃▃▃▂▂▁▁▁▁▁▁▂▂53.7452.21251.69451.87751.39648.11340.37340.71739.0137.69534.94735.82334.69334.76935.13933.92634.70634.69534.1731.53829.94628.57728.13728.39527.26327.93228.92331.70731.56
us-gaap:OtherAssetsCurrent ▂▃▂▂▂▇▇▇▃▃▄▄▂▃▂▂▂▂▂▂▂▃▂▁▂▁▂▃█51.96956.11747.90447.55747.652100.18896.83197.05456.05257.58669.21968.02452.6960.32447.91451.50550.85251.58549.77851.73149.10856.12148.24640.35443.51638.33444.78658.522107.201
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
us-gaap:PropertyPlantAndEquipmentGross ████▇▇▇▆▆▆▆▆▆▅▅▅▅▅▅▂▂▂▂▂▁▁▁▂▁12834.69512648.60412495.22712351.85211710.15511559.52811402.30811204.83810988.43510788.89410604.08910439.83910254.97610126.93110023.2529945.569816.2959704.1349620.0066954.186791.6376615.8136438.5256180.8275922.3085646.9185392.0656019.4535837.365
us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment ████▇▇▇▇▇▇▆▆▆▆▆▆▆▆▆▂▁▁▁▁▁▁▁▂▂6649.0386572.5346503.5616353.7856088.8036003.6585756.0845695.3285636.0655573.025520.4725462.6965411.7465344.1345294.2115271.4865232.7715185.0775133.8772007.5351935.4481876.011817.6551750.6361694.3661646.3941607.0882285.3132236.152
us-gaap:PropertyPlantAndEquipmentNet ██▇▇▆▆▇▆▆▅▅▅▄▄▄▄▄▃▃▅▄▄▄▃▃▂▁▁▁6185.6576076.075991.6665998.0675621.3525555.875646.2245509.515352.375215.8745083.6174977.1434843.234782.7974729.0414674.0744583.5244519.0574486.1294946.6454856.1894739.8034620.874430.1914227.9424000.5243784.9773734.143601.213
us-gaap:DeferredTaxAssetsLiabilitiesNet NANANA696.054NANANA653.382NANANA512.686NANANA-891.287NANANA-1145.353-1107.439-1055.002-1048.097-1020.508-976.884939.961-896.26NANA
 us-gaap:OperatingLeaseRightOfUseAsset us-gaap:BalanceSheetLocation nfg:DeferredChargesNANANA19.85NANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherAssetsNoncurrent NANA0.0810.0810.0810.08121.3540.0842.63242.18442.190.1020.1080.4260.7540.7420.4790.4850.4910.8430.9651.1052.4182.5942.651.531.6481.7471.836
 us-gaap:EquitySecuritiesFvNi us-gaap:InvestmentType nfg:EquityMutualFund▃▂▁▇▅▁▅██▇▄▆34.84932.99332.22639.61837.29131.95636.7440.6640.31338.89235.49838.468NANANANANANANANANANANANANANANANANA
 us-gaap:EquitySecuritiesFvNi us-gaap:InvestmentType us-gaap:EquitySecuritiesNA0.9880.8190.6390.6260.5770.9330.8441.841NANA2.776NANANANANANANANANANANANANANANANANA
 us-gaap:EquitySecuritiesFvNi us-gaap:InvestmentType us-gaap:FixedIncomeFunds▇▇▇█▆▅▅▅▂▂▂▁70.38870.13370.22372.25364.8463.09462.2262.33955.03454.16553.36751.331NANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
us-gaap:AccountsPayableCurrent ▃▂▂▄▁▂▄▄▃▅▄▆▃▄▄▄▂▃▃▂▂▁▁▂▂▄▂▄█113.47107.30596.905134.12694.123106.938126.985132.208112.782141.851127.926160.031111.812127.585132.409126.44398.842111.382113.13695.09594.90987.98588.11998.053105.209126.70995.182122.911181.564
 us-gaap:AccruedIncomeTaxesCurrent us-gaap:IncomeTaxAuthority us-gaap:InternalRevenueServiceIRSNANANA0.1630.159NANA0.0NANANA0.00.00.08.6881.7752.5739.355NANANANANANANANANANANA
us-gaap:AccruedLiabilitiesCurrent ▇▇▆▆▆▆▇▆▇██▆▂▂▂▂▂▂▂▂▂▁168.378176.94154.377140.176138.344150.239173.603139.6180.063195.797191.172132.69338.08333.67237.76138.67334.1833.17435.95121.89626.3184.386NANANA7.147NANANA
us-gaap:DividendsPayableCurrent █████▇▇▇▇▇▇▇▇▇▇▇▇▇▇▆▁▆▆▆▆▆▆▆▆41.48440.56240.5640.47540.4737.65437.6537.54737.54336.67836.66336.53236.52635.64135.5935.535.46934.57734.54430.4860.030.41630.39329.52729.47929.39929.35828.47828.407
us-gaap:LiabilitiesCurrent ▄▂█▃▁▄▄▂▂▂▂▃▅▂▂▅▄▁▁▂▆▆▅▆▂▄▃▄▄600.602402.972906.183459.573342.36583.818546.462421.908395.925432.998419.082440.06661.457379.895365.288646.039602.135325.895306.198373.398772.899734.479667.047726.462420.965528.618513.31603.618531.817
us-gaap:LongTermDebtCurrent NANA500.0NA0.00.00.00.00.00.00.00.0250.00.00.0300.0300.00.00.00.0250.0250.0250.0250.00.0150.0150.0150.0150.0
 us-gaap:LongTermDebtCurrent us-gaap:LongtermDebtType nfg:FourPointNinePercentNotesDueDecemberOneTwoThousandTwentyOneNANA500.0NANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:OperatingLeaseLiabilityCurrent us-gaap:BalanceSheetLocation us-gaap:OtherCurrentLiabilitiesNANANA4.943NANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:OtherAccruedLiabilitiesCurrent us-gaap:StatementBusinessSegments nfg:AccruedCapitalExpenditures▅▄▂▁▂▁▆▁▆▅█▂55.63249.52634.8433.34435.64531.88659.93333.71360.08252.87569.32138.354NANANA37.382NANANANANANANANANANANANANA
 us-gaap:OtherAccruedLiabilitiesCurrent us-gaap:StatementBusinessSegments nfg:OtherAccruals▅▄▆▄▂▁▃▂▄▃█▅35.69634.21539.02831.65424.06521.85628.61124.30433.65130.81847.68236.914NANANA38.673NANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
us-gaap:LiabilitiesNoncurrent ▆▆▆▅▅▅▄▄▃▂▂▁▂▁▁▃▄▃▃██▇▆▆▆▆▅▅▄1969.0991986.6781957.8871903.81921.9861909.9181839.7171767.5061663.471622.981588.9751527.7311549.6831530.4791482.2561669.8651793.371740.0751699.7592210.1782170.0882091.5682031.5661993.1472006.6421965.2391870.3441864.1841796.222
us-gaap:LongTermDebt █████▂▂▂▂▂▂▂▁▁▁▅▁2627.862627.0332630.4732629.5762628.7822134.9642134.3392133.7182133.1012132.4882131.882131.3652085.5822085.0122084.4652383.6812087.954NANANANA1399.0NANANA1049.0NANANA
us-gaap:LongTermDebtNoncurrent ██▄██▄▄▄▄▄▄▄▁▃▃▃▁2627.862627.0332130.4732629.5762628.7822134.9642134.3392133.7182133.1012132.4882131.882131.3651835.5822085.0122084.4652083.6811787.954NANA1649.01149.01149.01149.01149.01399.0899.0899.0899.0899.0
us-gaap:DeferredIncomeTaxLiabilitiesNet ▆▇▆▃██▄▁▁742.638763.441735.236696.054783.377777.299708.774653.382647.602NANA512.686NANANANANANANANANANANANANANANANANA
 us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent us-gaap:RetirementPlanType us-gaap:OtherPostretirementBenefitPlansDefinedBenefitNANANA4.872NANANA4.553NANANA4.919NANANA4.972NANANANANANANANANANANANANA
 us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent us-gaap:RetirementPlanType us-gaap:PensionPlansDefinedBenefitNANANA122.309NANANA129.176NANANA61.184NANANA144.107NANANANANANANANANANANANANA
 us-gaap:OperatingLeaseLiabilityNoncurrent us-gaap:BalanceSheetLocation us-gaap:OtherNoncurrentLiabilitiesNANANA14.777NANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo NANANA3.045NANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree NANANA2.507NANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour NANANA2.238NANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive NANANA2.086NANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive NANANA7.631NANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest ▆▇▆▅█▆█▇▇▇▆▅▅▅▄▂▂▂▁▆▆▅▅▅▅▄▄▄▃2011.1142098.9692044.6251971.9862225.8572079.9592182.142139.0252143.7512090.5092046.9911937.331927.3811919.1871859.9231703.7351684.0481651.321568.9432042.1132016.211960.0951989.241966.8871921.1481891.8851850.6111816.5151754.942
us-gaap:CommonStockValue █████▄▄▄▄▄▄▄▄▄▄▄▃▃▃▂▂▂▂▂▂▁▁▁▁91.17391.16491.15390.95590.94486.56286.55286.31586.30786.30186.27185.95785.94485.88285.76185.54385.46885.37585.29383.52283.48283.3383.2783.17483.03882.81382.782.54482.338
us-gaap:AdditionalPaidInCapital █████▅▅▅▄▄▄▄▄▄▄▄▄▄▄▂▂▁▁▁▁▁▁▁▁1012.7031009.0751004.3691004.158999.057835.444831.146832.264827.243821.837817.076820.223816.395810.126800.348796.646790.291782.688775.868676.615673.607669.501666.012660.495654.0650.749644.945645.961643.856
us-gaap:RetainedEarningsAccumulatedDeficit ▅▅▄▄▆▆▇▇▇▆▆▅▅▄▄▂▂▂▁█▇▇▇▇▆▆▆▆▅1145.71100.7181028.844991.631177.651176.871320.5921272.6011262.8671236.6571172.3341098.91097.4381070.9391014.733851.669841.593817.348762.6411398.9991343.7651306.2841287.8981275.1071237.2421206.0221198.0641180.5311093.398
us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax ▁▄▅▄▆▆▅▆▆▆▆▅▅▆▆▆▆▆▅▄▅▄▆▆▆█▅▅▅-238.462-101.988-79.741-114.757-41.794-18.917-56.15-52.155-32.666-54.286-28.69-67.75-72.396-47.76-40.919-30.123-33.304-34.091-54.859-117.023-84.644-99.02-47.94-51.889-53.13247.699-75.098-92.521-64.65
 us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents us-gaap:AccumulatedDefinedBenefitPlansAdjustment▁▁▁▁▁▁▁▁▆▆██▆▆▆▆▃▃▃-89.892-89.892-89.892-89.892-86.83-86.83-86.83-86.83-58.848-58.848-46.576-46.576-58.486-58.486-58.486-58.486-76.476-76.476-76.476NANANANANANANANANANA
 us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents us-gaap:AccumulatedGainLossNetCashFlowHedgeParent▁▅▆▅▇█▇▇-148.57-12.09610.151-24.86545.03667.91330.6834.675NANANANANANANANANANANANANANANANANANANANANA
 us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents us-gaap:AccumulatedOtherComprehensiveIncome▁▅▆▅▇█▇▇█▇█▆▆▇▇█-238.462-101.988-79.741-114.757-41.794-18.917-56.15-52.155-32.666-54.286-28.69-67.75-72.396-47.76-40.919-30.123NANANANANA-99.02NANANA-47.699NANANA
 us-gaap:StockIssuedDuringPeriodValueNewIssues us-gaap:StatementEquityComponents us-gaap:AdditionalPaidInCapitalNANANA-0.089161.488NANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:StockIssuedDuringPeriodValueNewIssues us-gaap:StatementEquityComponents us-gaap:CommonStockNANANA0.04.37NANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
us-gaap:NetCashProvidedByUsedInOperatingActivities █▆▆▂▇▇▄▂▇▇▁254.677212.39204.743116.939232.878223.243167.749123.928229.72236.463104.372NANANANANANANANA220.895145.96119.797202.093259.66979.228141.004193.06255.75187.471
us-gaap:NetCashProvidedByUsedInInvestingActivities ▇▇█▁▇▆▆▆▆▆▇-174.78-155.32-66.87-649.688-182.609-198.036-193.283-208.662-201.318-209.079-180.116NANANANANANANANA-176.668-166.514-258.175-277.767-266.76-233.636-259.807-121.777-143.97-192.1
us-gaap:NetCashProvidedByUsedInFinancingActivities ▂▁▂▂█▃▃▃▂▂▂-40.642-86.016-49.001-10.673391.31152.54442.90617.644-36.678-37.296-44.765NANANANANANANANA7.1697.07772.05724.246-24.928298.24214.521-31.34-48.636-210.92
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
 us-gaap:DeferredIncomeTaxExpenseBenefit us-gaap:ImpairedLongLivedAssetsHeldAndUsedByType nfg:ImpairmentofOilandGasProducingPropertiesNANA21.069.65.0NANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:DepreciationDepletionAndAmortization ███▇▅▇▆▆▅▄▃▃▃▃▂▁▂▂▂▇▅▅▆▃▃▂▂▃▁84.1784.34283.1280.09673.23277.91274.91874.6771.07265.66464.25563.15960.81761.15555.8355.38355.61756.99956.19680.0372.33171.60574.22763.15162.54755.9157.29360.01153.313
us-gaap:IncreaseDecreaseInInventories ▆▄▃▇▆▄▄▇▆▃▄▇▆▃▄▇▆▃▄▂▄▇▅▁▅█▆▁▅8.234-13.385-13.87318.2228.489-13.101-6.98521.26411.542-20.74-8.35322.8539.172-17.667-10.33717.1168.777-13.879-10.597-28.45-3.94125.4486.303-39.3822.22632.3217.757-35.9725.828
us-gaap:NetCashProvidedByUsedInOperatingActivities █▆▆▂▇▇▄▂▇▇▁254.677212.39204.743116.939232.878223.243167.749123.928229.72236.463104.372NANANANANANANANA220.895145.96119.797202.093259.66979.228141.004193.06255.75187.471
us-gaap:NetIncomeLoss ▆▆▆▁▅▂▆▅▅▆▆▅▅▆█▅▅▆▆▆▅▅▅▅▅▅▅▆▅86.475112.43677.774-145.54541.25-106.06886.59147.28263.75390.595102.6637.99563.02591.847198.65445.57759.71489.28488.90885.7267.94448.80243.18467.39260.69937.35646.891115.61158.543
us-gaap:ShareBasedCompensation ▄▇▅█▁▆▃▇███▅▅▅▅▄▃▃▂▃▃3.6394.7243.9335.2152.1364.3143.2665.0425.4135.425.3113.9923.9083.9573.9053.4053.2253.152.4823.2943.302NANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
us-gaap:NetCashProvidedByUsedInInvestingActivities ▇▇█▁▇▆▆▆▆▆▇-174.78-155.32-66.87-649.688-182.609-198.036-193.283-208.662-201.318-209.079-180.116NANANANANANANANA-176.668-166.514-258.175-277.767-266.76-233.636-259.807-121.777-143.97-192.1
us-gaap:PaymentsToAcquirePropertyPlantAndEquipment ▄▃▄▄▃▅▅▅▅▅▄▄▃▂▃▂▁▁▁▄▃▇██▆▇▅▅▅173.908155.566183.301165.149155.518196.991198.495201.496200.863209.012177.567180.01142.274119.107142.613135.561106.543102.178106.053176.756162.981259.888277.289266.937232.67253.873191.401200.286192.052
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
us-gaap:NetCashProvidedByUsedInFinancingActivities ▂▁▂▂█▃▃▃▂▂▂-40.642-86.016-49.001-10.673391.31152.54442.90617.644-36.678-37.296-44.765NANANANANANANANA7.1697.07772.05724.246-24.928298.24214.521-31.34-48.636-210.92
us-gaap:ProceedsFromIssuanceOfLongTermDebt 0.0NANA-0.101NANANA0.0NANANANANANANANANANANA495.4150.00.00.00.0496.0850.00.00.00.0
 us-gaap:ProceedsFromIssuanceOfLongTermDebt us-gaap:LongtermDebtType nfg:TwoPointNineFivePercentNotesDueMarchFirstTwoThousandThirtyOneNANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:RepaymentsOfLongTermDebt 0.0NANANANANANA0.00.00.00.0259.4650.00.0307.0470.00.00.00.0250.00.00.00.00.0150.00.00.00.0200.0
us-gaap:PaymentsOfDividendsCommonStock ▆▆▆▆▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▁█▄▄▄▄▄▄▄▄40.57140.5640.47540.47137.65437.6537.54737.54336.67836.66536.53236.52635.64135.59135.535.46934.57734.54434.4730.060.87930.39429.52729.47929.39829.35828.47828.40728.316
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:LongtermDebtType nfg:FourPointNinePercentNotesDueDecemberFirstTwoThousandTwentyOneNANANA4.9000000000000005e-06NANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:LongtermDebtType nfg:SevenPointFourPercentDueMarchTwoThousandTwentyThreeToJuneTwoThousandTwentyFiveNANANA7.4e-06NANANA7.4e-08NANANA7.4e-08NANANA7.4e-08NANANANANANANANANANANANANA
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:LongtermDebtType nfg:TwoPointNineFivePercentNotesDueMarchFirstTwoThousandThirtyOneNANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

Common Stock Value

us-gaap:CommonStockValue

us-gaap:CommonStockValue


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value9191919090868686868686858585858585858585848484848484848484838383838383838383838282828282
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 Assets1.31.31.31.31.31.31.31.31.41.41.41.41.41.51.51.41.51.51.51.51.51.51.41.31.21.21.21.21.31.31.31.31.31.31.41.41.41.41.41.61.61.61.71.6

Common Stock Shares Outstanding

us-gaap:CommonStockSharesOutstanding us-gaap:StatementEquityComponents

us-gaap:CommonStockSharesOutstanding

us-gaap:CommonStock


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-302010-09-302009-09-302008-09-30
Value91919190908686868686868585858585858484838382828079
Percentage of CommonStockSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Diluted Shares Outstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding


Weighted
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-312019-06-302019-03-312018-12-312018-06-302018-03-312017-12-312017-06-302017-03-312016-12-312016-06-302016-03-312015-12-312015-06-302015-03-312014-12-312014-06-302014-03-312013-12-312013-06-302013-03-312012-12-312012-06-302012-03-312011-12-312011-06-302011-03-312010-12-312010-06-302010-03-312009-12-31
Value919191888686868686868686868685858484858585848484848484838383838383828282
Percentage of WeightedAverageNumberOfDilutedSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Shares Outstanding Basic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic


Weighted
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-312019-06-302019-03-312018-12-312018-06-302018-03-312017-12-312017-06-302017-03-312016-12-312016-06-302016-03-312015-12-312015-06-302015-03-312014-12-312014-06-302014-03-312013-12-312013-06-302013-03-312012-12-312012-06-302012-03-312011-12-312011-06-302011-03-312010-12-312010-06-302010-03-312009-12-31
Value919191878686868686858585858585848484848484848383838383838382828282818180
Percentage of WeightedAverageNumberOfSharesOutstandingBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Basic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareBasic


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value0.951.230.85-1.60.47-1.231.00.550.741.051.190.440.731.072.320.530.71.051.040.440.1-1.74-2.23-2.22-3.470.21.010.680.771.140.980.570.71.030.810.590.520.810.730.450.571.40.710.470.520.990.8
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Diluted

us-gaap:EarningsPerShareDiluted

us-gaap:EarningsPerShareDiluted


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value0.941.230.85-1.60.47-1.231.00.540.731.041.180.440.731.062.30.530.691.041.040.440.1-1.74-2.23-2.22-3.440.21.00.680.761.120.970.570.691.020.810.580.520.810.730.450.561.380.70.460.510.970.78
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Allocated Share Based Compensation Expense

us-gaap:AllocatedShareBasedCompensationExpense us-gaap:StatementEquityComponents

us-gaap:AllocatedShareBasedCompensationExpense

us-gaap:AdditionalPaidInCapital


Allocated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value3.1964.2833.4964.7771.6993.8762.8284.6055.0545.0384.9173.6033.5583.5633.511
Percentage of AllocatedShareBasedCompensationExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.80.80.81.70.50.80.61.61.40.91.01.21.00.70.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value-49.99990112-218.50818-68.8358227856414142388518748601103924-66.161-163.957-184.025-186.579-327.5752021197657279871165382-2.2784768556464873831439454
Percentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-12.716.425.6-75.95.7-14.018.69.523.911.828.414.711.215.744.817.017.421.19.40.00.00.00.00.00.00.00.00.00.00.00.00.00.08.918.20.014.312.412.80.016.913.38.60.00.00.00.0

Cost Of Goods And Services Sold

us-gaap:CostOfGoodsAndServicesSold

us-gaap:CostOfGoodsAndServicesSold


Cost
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value1810651-5.77329118924.72847195
Percentage of CostOfGoodsAndServicesSold100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax4.819.411.7-2.09.024.120.81.613.435.3

us-gaap:CostOfGoodsAndServicesSold us-gaap:ProductOrService, us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:OilAndGasPurchased, us-gaap:CommodityContract, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Cost
Period End2020-09-302020-06-302020-03-312019-12-31
Value-1.229-0.0221.9090.002
Percentage of CostOfGoodsAndServicesSold21.3-0.11.60.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.4-0.00.40.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OilAndGasPurchased us-gaap:CommodityContract us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.0

Costs And Expenses

us-gaap:CostsAndExpenses

us-gaap:CostsAndExpenses


Costs
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value244337348461242515296209244399
Percentage of CostsAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax61.961.279.0160.475.1105.066.771.468.472.2

Gains Losses On Extinguishment Of Debt

us-gaap:GainsLossesOnExtinguishmentOfDebt

us-gaap:GainsLossesOnExtinguishmentOfDebt


Gains
Period End2021-06-30
Value0
Percentage of GainsLossesOnExtinguishmentOfDebt0.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0

us-gaap:GainsLossesOnExtinguishmentOfDebt us-gaap:LongtermDebtType

nfg:FourPointNinePercentNotesDueDecemberOneTwoThousandTwentyOne


Gains
Period End2021-06-30
Value0
Percentage of GainsLossesOnExtinguishmentOfDebt0.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:FourPointNinePercentNotesDueDecemberOneTwoThousandTwentyOne0.0

Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value116152107-208.18254-69.2221175884120125548213011761951421455617-263.717-333.459-350.229-510.041211398410516113776104
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax29.627.724.3-72.316.8-14.126.620.023.821.825.118.824.024.128.021.327.427.234.40.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value-13.129-3.666-0.3119.20136257.3527.7023.869-4.739-8.779-16.47-3.771-3.199129.36518103135586157475054244.749-14.48-26.6410
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest-11.2-2.4-0.3-4.466.8-36.26.213.14.6-3.9-7.0-30.3-4.6-2.511.115.319.37.421.661.9342.8-23.4-17.1-13.4-10.0248.217.35.6-13.7-16.57.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-3.3-0.7-0.13.211.35.11.72.61.1-0.9-1.8-5.7-1.1-0.63.13.35.32.07.40.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Income Tax Expense Benefit

us-gaap:IncomeTaxExpenseBenefit

us-gaap:IncomeTaxExpenseBenefit


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value304029-62.63713363111212922161938-81.27715355256198.74-116.03-144.35-162.526-216.9075.136552641665528455543382644402331723821254939
Percentage of IncomeTaxExpenseBenefit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax7.77.36.7-21.74.17.57.13.95.95.44.65.65.67.1-19.45.410.310.113.40.00.00.00.00.00.00.00.00.00.00.00.00.00.09.29.60.08.08.19.40.08.110.98.40.00.00.00.0

us-gaap:IncomeTaxExpenseBenefit us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value-3.617-1.01-0.0863.1999.9076.8172.0311.3321.113-1.328-1.493-4.92-1.208-0.5515.3554.6047.6934.4141315242518202122102.498-8.269-11.174.299
Percentage of IncomeTaxExpenseBenefit-11.9-2.5-0.3-5.175.418.56.511.75.3-4.5-6.5-30.1-6.3-1.4-6.629.721.58.323.479.5280.5-22.2-12.5-12.5-10.1446.218.39.3-20.1-16.97.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.9-0.2-0.01.13.11.40.50.50.3-0.2-0.3-1.7-0.4-0.11.31.62.20.83.10.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Interest Expense Long Term Debt

us-gaap:InterestExpenseLongTermDebt

us-gaap:InterestExpenseLongTermDebt


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value3048323227252525252525282727282929282929282830292222222222222223222221212120181717172021212222
Percentage of InterestExpenseLongTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax7.78.97.311.28.45.15.78.77.14.65.19.97.95.06.710.28.45.56.90.00.00.00.00.00.00.00.00.00.00.00.00.00.03.84.70.06.53.74.30.04.72.74.50.00.00.00.0

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value8611277-145.54541-106.0688647639010237639119845598988378.286-147.687-189.109-187.703-293.134168457649582475885674843676037461155838428064
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax21.920.417.6-50.512.8-21.619.516.117.816.420.513.118.417.047.315.917.117.121.00.00.00.00.00.00.00.00.00.00.00.00.00.00.014.315.00.013.112.214.00.012.317.513.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value-9.512-2.656-0.2256.00226185.3216.372.756-3.411-7.286-11.55-2.563-2.6487.6234.761106.0581819333539262931142.251-6.211-15.475.884
Percentage of NetIncomeLoss-11.0-2.4-0.3-4.164.1-17.26.113.54.3-3.8-7.1-30.4-4.1-2.93.810.418.06.820.552.9408.6-24.3-20.7-14.2-9.9187.316.73.9-9.6-16.27.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2.4-0.5-0.12.18.23.71.22.20.8-0.6-1.5-4.0-0.7-0.51.81.73.11.24.30.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:StatementBusinessSegments

nfg:AllOther


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value1.039-0.98337-1.801-0.0091.1690.371-2.063-0.003-0.1280.3840.1020.2970.207-0.7190.156-0.098-0.221-0.1790.1830.43-0.0230.189-0.068-0.0280.098-0.0060.1820.0240.2780.675-8.5554.4993.0641.885-5.5442.8151.3391.404-0.6912.71332-0.574
Percentage of NetIncomeLoss1.2-0.948.31.2-0.0-1.10.4-4.4-0.0-0.10.40.30.50.2-0.40.3-0.2-0.2-0.20.55.20.0-0.10.00.00.6-0.00.30.00.30.8-17.97.73.62.8-11.46.52.02.3-1.85.827.8-1.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.3-0.28.5-0.6-0.00.20.1-0.7-0.0-0.00.10.00.10.0-0.20.1-0.0-0.0-0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.50.40.00.90.20.30.00.74.9-0.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:AllOther103900.0-1512.33323.90.0-0.03.11.10.0-0.4-41.338.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0402.6185.70.0341.6130.9149.80.0144.86818.0-104.6

nfg:CorporateAndIntersegmentEliminations


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value-0.795-1.0752.067-1.1993.577-5.4461.611-1.6030.8932.278-0.57-3.681-1.118-3.329-13.226-2.947-0.233-0.2910.701-3.174-1.3641.4651.762-3.444-1.193-1.260.205-6.182-0.0042.537-0.624-1.142-0.406-0.65-0.927-5.056-0.192-0.565-0.761-5.546-1.328-0.204-0.756
Percentage of NetIncomeLoss-0.9-1.02.70.88.75.11.9-3.41.42.5-0.6-9.7-1.8-3.6-6.7-6.5-0.4-0.30.8-8.5-16.5-1.0-0.91.80.4-7.60.2-10.8-0.02.7-0.8-2.4-0.7-0.8-1.4-10.4-0.4-0.8-1.3-14.8-2.8-0.2-1.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.2-0.20.5-0.41.1-1.10.4-0.50.20.4-0.1-1.3-0.3-0.6-3.2-1.0-0.1-0.10.20.00.00.00.00.00.00.00.00.00.00.00.00.00.0-0.1-0.20.0-0.1-0.1-0.20.0-0.3-0.0-0.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:CorporateAndIntersegmentEliminations1.11.4-2.80.0-5.78.2-2.70.0-1.5-4.01.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0-290.2-461.20.0-80.0-244.6-298.40.0-558.0-83.6-337.5

nfg:ExplorationAndProduction


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value3936-29.623-169.171-6.434-175.27523252621381927261063030333516-19.165-213.335-237.086-207.019-323.113-53.5622633322431293127262221223030323327
Percentage of NetIncomeLoss45.132.7-38.1116.2-15.6165.227.753.341.624.137.251.544.128.953.766.650.437.839.544.6-231.3144.5125.4110.3110.2-321.331.558.650.225.637.861.254.332.339.345.250.732.949.982.369.928.846.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax9.96.7-6.7-58.7-2.0-35.75.48.67.44.07.66.88.14.925.410.68.66.58.30.00.00.00.00.00.00.00.00.00.00.00.00.00.04.65.90.06.74.07.00.08.65.06.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:ExplorationAndProduction17.516.4-15.50.0-6.8-132.615.10.017.313.821.90.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

nfg:Gathering


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value2020201715191516141214141111459.0041010108.5379.4737.5684.9217.5956.2266.40511108.7177.3246.1473.8794.4073.0931.942
Percentage of NetIncomeLoss23.618.426.4-12.136.9-18.818.435.723.014.013.838.918.412.822.919.816.911.512.422.7114.3-5.1-2.6-4.0-2.138.413.718.313.57.77.58.17.53.62.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax5.23.84.76.14.74.13.65.84.12.32.85.13.42.210.83.12.92.02.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.50.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:Gathering42.041.243.70.045.856.445.80.044.543.247.80.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

nfg:PipelineAndStorage


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value21242416222218151517251520223813161919161721211817232019172119151416162512129.9597.4794.503108.578
Percentage of NetIncomeLoss25.422.231.1-11.054.8-20.820.932.524.819.624.540.432.924.719.430.326.821.621.844.8209.1-14.4-11.3-9.8-6.0140.224.533.327.822.423.332.324.119.624.951.429.219.116.420.09.69.514.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax5.64.55.55.67.04.54.15.24.43.25.05.36.04.29.24.84.63.74.60.00.00.00.00.00.00.00.00.00.00.00.00.00.02.83.70.03.82.32.30.01.21.71.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:PipelineAndStorage26.128.827.60.029.127.925.10.022.924.532.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.036.239.00.034.530.528.30.015.027.625.6

nfg:TotalReportableSegments


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value8611438-142.54537-101.7918450628810241639421248608988409.22-149.129-191.06-184.191-291.913178463649282575483665940666043458359
Percentage of NetIncomeLoss99.7101.849.097.991.496.097.7107.898.697.6100.2109.4101.3103.4107.0106.1100.6100.699.4108.0111.3101.0101.098.199.6107.099.8110.4100.097.099.9120.393.097.298.6121.793.998.998.9116.797.072.3102.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax21.920.88.6-49.511.7-20.719.017.417.616.020.614.418.617.650.716.917.217.220.90.00.00.00.00.00.00.00.00.00.00.00.00.00.013.914.80.012.312.113.90.011.912.713.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:TotalReportableSegments0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

nfg:Utility


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value4.8413223-6.9696.2543126-7.7297.3623525-7.0663.933320-4.1684.3482521-1.7852.1793118-3.2875.7273822-0.5274.82635240.6627.6334225.8655.09628190.8296.3283322
Percentage of NetIncomeLoss5.628.529.64.815.2-29.730.7-16.311.539.325.0-18.66.236.310.6-9.17.328.723.8-4.826.3-21.6-9.81.8-2.0229.426.7-0.97.537.329.41.413.040.333.712.011.842.031.92.213.528.639.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.25.85.2-2.41.96.46.0-2.62.16.45.1-2.41.16.25.0-1.51.24.95.00.00.00.00.00.00.00.00.00.00.00.00.00.00.05.85.10.01.55.14.50.01.75.05.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:Utility3.911.912.60.04.912.613.70.05.611.711.50.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value8611277-145.54541-106.06886476390102376391198
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax21.920.417.6-50.512.8-21.619.516.117.816.420.513.118.417.047.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Operating Income Loss

us-gaap:OperatingIncomeLoss

us-gaap:OperatingIncomeLoss


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value150214143-173.97980-24.581488311215316180107156141871231691728145-237.0-305.924-326.731-489.21444160102127180160961271621311079013211875941531177389151125
Percentage of OperatingIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax38.138.832.5-60.424.9-5.033.328.631.627.832.427.931.429.033.830.535.432.640.70.00.00.00.00.00.00.00.00.00.00.00.00.00.027.329.00.027.523.927.40.024.923.326.00.00.00.00.0

Other Comprehensive Income Loss Net Of Tax

us-gaap:OtherComprehensiveIncomeLossNetOfTax

us-gaap:OtherComprehensiveIncomeLossNetOfTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-136.474-22.24735-72.963-22.87737-3.995-19.48921-25.596394.646-24.636-6.841-10.7963.1810.78720-49.219-13.379-74.447-16.275.0841.124-34.4414.216126391.417-23.017-2.8043958-32.37914-51.083.9491.244-5.4332717-27.871
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-34.6-4.07.9-25.3-7.17.6-0.9-6.66.1-4.67.81.6-7.2-1.3-2.61.10.24.0-11.60.00.00.00.00.00.00.00.00.00.00.00.00.00.0-5.43.20.01.20.2-1.30.04.6-4.2

us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-136.474-22.24735-72.963-22.87737-3.995-19.48921-25.596394.646-24.636-6.841-10.796
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-34.6-4.07.9-25.3-7.17.6-0.9-6.66.1-4.67.81.6-7.2-1.3-2.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Other Nonoperating Income Expense

us-gaap:OtherNonoperatingIncomeExpense

us-gaap:OtherNonoperatingIncomeExpense


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-2028000.0-10875000.0-2176000.0157000.02547000.0-17480000.0-3040000.01435000.0-1456000.0-5919000.0-9602000.0-969000.0-3612000.0-13092000.0-3503000.0
Percentage of OtherNonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.5-2.0-0.50.10.8-3.6-0.70.5-0.4-1.1-1.9-0.3-1.1-2.4-0.8

Revenue From Contract With Customer Excluding Assessed Tax

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value394551441287323491444293357552499289342540419286348522422597452313328552432286380660450
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

nfg:NaturalGasCommercialSales, nfg:TotalConsolidated


Revenue
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-31
Value102817102718
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.75.23.93.25.64.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.75.23.93.25.64.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:NaturalGasCommercialSales nfg:TotalConsolidated100.0100.0100.0100.0100.0100.0

nfg:NaturalGasCommercialSales, nfg:Utility


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value1028174.8381027184.923123422
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.75.23.91.73.25.64.21.73.46.24.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.75.23.91.73.25.64.21.73.46.24.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:NaturalGasCommercialSales nfg:Utility100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:NaturalGasCommercialSales, us-gaap:ConsolidatedEntities


Revenue
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value4.8381027184.923123422
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.73.25.64.21.73.46.24.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.73.25.64.21.73.46.24.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:NaturalGasCommercialSales us-gaap:ConsolidatedEntities100.0100.0100.0100.0100.0100.0100.0100.0

nfg:NaturalGasIndustrialSales, nfg:TotalConsolidated


Revenue
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-31
Value0.4881.3680.9220.6161.1441.27
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.20.20.20.20.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.20.20.20.20.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:NaturalGasIndustrialSales nfg:TotalConsolidated100.0100.0100.0100.0100.0100.0

nfg:NaturalGasIndustrialSales, nfg:Utility


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0.4881.3680.9220.2620.6161.1441.270.431.0321.8671.501
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.20.20.10.20.20.30.10.30.30.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.20.20.10.20.20.30.10.30.30.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:NaturalGasIndustrialSales nfg:Utility100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:NaturalGasIndustrialSales, us-gaap:ConsolidatedEntities


Revenue
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0.2620.6161.1441.270.431.0321.8671.501
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.20.20.30.10.30.30.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.20.20.30.10.30.30.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:NaturalGasIndustrialSales us-gaap:ConsolidatedEntities100.0100.0100.0100.0100.0100.0100.0100.0

nfg:NaturalGasProcessing, nfg:ExplorationAndProduction


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0.7320.7720.5530.5360.4350.7140.6880.6010.7310.9710.975
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.20.10.10.20.10.10.20.20.20.20.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.20.10.10.20.10.10.20.20.20.20.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:NaturalGasProcessing nfg:ExplorationAndProduction100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:NaturalGasProcessing, nfg:TotalConsolidated


Revenue
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-31
Value0.7320.7720.5530.4350.7140.688
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.20.10.10.10.10.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.20.10.10.10.10.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:NaturalGasProcessing nfg:TotalConsolidated100.0100.0100.0100.0100.0100.0

nfg:NaturalGasProcessing, us-gaap:ConsolidatedEntities


Revenue
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0.5360.4350.7140.6880.6010.7310.9710.975
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.20.10.10.20.20.20.20.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.20.10.10.20.20.20.20.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:NaturalGasProcessing us-gaap:ConsolidatedEntities100.0100.0100.0100.0100.0100.0100.0100.0

nfg:NaturalGasResidentialSales, nfg:TotalConsolidated


Revenue
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-31
Value9320313793185144
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax23.637.031.329.137.732.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax23.637.031.329.137.732.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:NaturalGasResidentialSales nfg:TotalConsolidated100.0100.0100.0100.0100.0100.0

nfg:NaturalGasResidentialSales, nfg:Utility


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value9320313752931851444796229166
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax23.637.031.318.229.137.732.516.326.941.533.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax23.637.031.318.229.137.732.516.326.941.533.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:NaturalGasResidentialSales nfg:Utility100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:NaturalGasResidentialSales, us-gaap:ConsolidatedEntities


Revenue
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value52931851444796229166
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax18.229.137.732.516.326.941.533.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax18.229.137.732.516.326.941.533.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:NaturalGasResidentialSales us-gaap:ConsolidatedEntities100.0100.0100.0100.0100.0100.0100.0100.0

nfg:ProductionofCrudeOil, nfg:ExplorationAndProduction


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value3733242217303737383437
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax9.66.15.67.95.36.28.512.910.96.37.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax9.66.15.67.95.36.28.512.910.96.37.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:ProductionofCrudeOil nfg:ExplorationAndProduction100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:ProductionofCrudeOil, nfg:TotalConsolidated


Revenue
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-31
Value373324173037
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax9.66.15.65.36.28.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax9.66.15.65.36.28.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:ProductionofCrudeOil nfg:TotalConsolidated100.0100.0100.0100.0100.0100.0

nfg:ProductionofCrudeOil, us-gaap:ConsolidatedEntities


Revenue
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value2217303737383437
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax7.95.36.28.512.910.96.37.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax7.95.36.28.512.910.96.37.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:ProductionofCrudeOil us-gaap:ConsolidatedEntities100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NaturalGasMidstream, nfg:CorporateAndIntersegmentEliminations


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value-48.068-49.591-46.658-39.466-33.299-35.267-34.788-35.133-32.875-29.366-29.69
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-12.2-9.0-10.6-13.7-10.3-7.2-7.8-12.0-9.2-5.3-5.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-12.2-9.0-10.6-13.7-10.3-7.2-7.8-12.0-9.2-5.3-5.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:NaturalGasMidstream nfg:CorporateAndIntersegmentEliminations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NaturalGasMidstream, nfg:Gathering


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value4850473933353435322929
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax12.39.110.713.710.37.27.812.09.25.35.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax12.39.110.713.710.37.27.812.09.25.35.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:NaturalGasMidstream nfg:Gathering100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NaturalGasMidstream, nfg:TotalConsolidated


Revenue
Period End2021-06-302021-03-312020-12-31
Value0.5880.6710.351
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:NaturalGasMidstream nfg:TotalConsolidated100.0100.0100.0

us-gaap:NaturalGasMidstream, us-gaap:ConsolidatedEntities


Revenue
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0.0720.00.00.00.00.00.0020.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:NaturalGasMidstream us-gaap:ConsolidatedEntities100.00.00.00.00.00.0100.00.0

us-gaap:NaturalGasProduction, nfg:ExplorationAndProduction


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value18418816610476100119109113121135
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax46.734.337.736.423.820.527.037.331.922.027.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax46.734.337.736.423.820.527.037.331.922.027.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:NaturalGasProduction nfg:ExplorationAndProduction100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NaturalGasProduction, nfg:TotalConsolidated


Revenue
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-31
Value18418816676100119
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax46.734.337.723.820.527.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax46.734.337.723.820.527.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:NaturalGasProduction nfg:TotalConsolidated100.0100.0100.0100.0100.0100.0

us-gaap:NaturalGasProduction, us-gaap:ConsolidatedEntities


Revenue
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value10476100119109113121135
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax36.423.820.527.037.331.922.027.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax36.423.820.527.037.331.922.027.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:NaturalGasProduction us-gaap:ConsolidatedEntities100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NaturalGasStorage, nfg:CorporateAndIntersegmentEliminations


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value-8.926-9.108-8.763-8.698-8.802-9.087-7.993-8.121-8.06-8.333-7.973
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2.3-1.7-2.0-3.0-2.7-1.9-1.8-2.8-2.3-1.5-1.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2.3-1.7-2.0-3.0-2.7-1.9-1.8-2.8-2.3-1.5-1.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:NaturalGasStorage nfg:CorporateAndIntersegmentEliminations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NaturalGasStorage, nfg:PipelineAndStorage


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value2021202020201818181918
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax5.23.94.77.06.24.24.16.35.23.53.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax5.23.94.77.06.24.24.16.35.23.53.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:NaturalGasStorage nfg:PipelineAndStorage100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NaturalGasStorage, nfg:TotalConsolidated


Revenue
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-31
Value111211111110
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.02.22.73.52.32.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.02.22.73.52.32.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:NaturalGasStorage nfg:TotalConsolidated100.0100.0100.0100.0100.0100.0

us-gaap:NaturalGasStorage, us-gaap:ConsolidatedEntities


Revenue
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value1111111010101110
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax4.03.52.32.33.63.02.02.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax4.03.52.32.33.63.02.02.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:NaturalGasStorage us-gaap:ConsolidatedEntities100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OilAndGasRefiningAndMarketing, nfg:AllOther


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0.0010.0660.5856.0651936341430.05849
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.12.15.97.47.749.00.010.69.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.12.15.97.47.749.00.010.69.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OilAndGasRefiningAndMarketing nfg:AllOther100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0

us-gaap:OilAndGasRefiningAndMarketing, nfg:CorporateAndIntersegmentEliminations


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value-0.002-0.001-0.02-0.237-0.341-0.079-0.177-0.071-0.681-0.043-0.332
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.0-0.0-0.0-0.1-0.1-0.0-0.0-0.0-0.2-0.0-0.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.0-0.0-0.0-0.1-0.1-0.0-0.0-0.0-0.2-0.0-0.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OilAndGasRefiningAndMarketing nfg:CorporateAndIntersegmentEliminations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OilAndGasRefiningAndMarketing, nfg:TotalConsolidated


Revenue
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-31
Value-0.0010.0650.565183633
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.00.00.15.87.47.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.00.00.15.87.47.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OilAndGasRefiningAndMarketing nfg:TotalConsolidated100.0100.0100.0100.0100.0100.0

us-gaap:OilAndGasRefiningAndMarketing, us-gaap:ConsolidatedEntities


Revenue
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value5.82818363313215848
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.05.87.47.64.66.010.69.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.05.87.47.64.66.010.69.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OilAndGasRefiningAndMarketing us-gaap:ConsolidatedEntities100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OilAndGasService, nfg:CorporateAndIntersegmentEliminations


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value-17.786-18.187-19.59-18.291-20.445-21.976-16.986-16.133-17.672-19.819-17.065
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-4.5-3.3-4.4-6.4-6.3-4.5-3.8-5.5-4.9-3.6-3.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-4.5-3.3-4.4-6.4-6.3-4.5-3.8-5.5-4.9-3.6-3.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OilAndGasService nfg:CorporateAndIntersegmentEliminations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OilAndGasService, nfg:PipelineAndStorage


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value6364645957585350505256
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax16.011.714.720.817.811.912.017.314.09.511.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax16.011.714.720.817.811.912.017.314.09.511.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OilAndGasService nfg:PipelineAndStorage100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OilAndGasService, nfg:TotalConsolidated


Revenue
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-31
Value658574597669
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax16.615.616.818.415.515.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax16.615.616.818.415.515.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OilAndGasService nfg:TotalConsolidated100.0100.0100.0100.0100.0100.0

us-gaap:OilAndGasService, nfg:Utility


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value2039291422393215234535
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax5.17.26.64.97.08.17.45.36.48.27.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax5.17.26.64.97.08.17.45.36.48.27.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OilAndGasService nfg:Utility100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OilAndGasService, us-gaap:ConsolidatedEntities


Revenue
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value5559766950557774
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax19.418.415.515.617.115.514.015.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax19.418.415.515.617.115.514.015.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OilAndGasService us-gaap:ConsolidatedEntities100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProductAndServiceOther, nfg:AllOther


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0.0-0.0010.5452.1891.0150.8511.121.2540.8540.311.007
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0-0.00.10.80.30.20.30.40.20.10.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0-0.00.10.80.30.20.30.40.20.10.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductAndServiceOther nfg:AllOther0.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProductAndServiceOther, nfg:CorporateAndIntersegmentEliminations


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value-0.084-0.097-0.108-0.078-0.098-0.065-0.052-0.02-0.02-0.105-0.404
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductAndServiceOther nfg:CorporateAndIntersegmentEliminations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProductAndServiceOther, nfg:ExplorationAndProduction


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0.360.8180.2110.30.2180.4050.1720.5810.1520.4930.382
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.10.00.10.10.10.00.20.00.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.10.00.10.10.10.00.20.00.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductAndServiceOther nfg:ExplorationAndProduction100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProductAndServiceOther, nfg:PipelineAndStorage


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0.310.8252.4220.2970.2340.2670.3420.5030.3680.742.005
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.10.50.10.10.10.10.20.10.10.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.10.50.10.10.10.10.20.10.10.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductAndServiceOther nfg:PipelineAndStorage100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProductAndServiceOther, nfg:TotalConsolidated


Revenue
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-31
Value0.149-2.9741.4580.708-2.066-1.742
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0-0.50.30.2-0.4-0.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0-0.50.30.2-0.4-0.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductAndServiceOther nfg:TotalConsolidated100.0100.0100.0100.0100.0100.0

us-gaap:ProductAndServiceOther, nfg:Utility


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value-0.437-4.519-1.6122.228-0.661-3.524-3.3240.0320.161-5.963-2.861
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.1-0.8-0.40.8-0.2-0.7-0.70.00.0-1.1-0.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.1-0.8-0.40.8-0.2-0.7-0.70.00.0-1.1-0.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductAndServiceOther nfg:Utility100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProductAndServiceOther, us-gaap:ConsolidatedEntities


Revenue
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value4.9360.708-2.066-1.7422.3441.52-4.5170.129
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.70.2-0.4-0.40.80.4-0.80.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.70.2-0.4-0.40.80.4-0.80.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductAndServiceOther us-gaap:ConsolidatedEntities100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:StatementBusinessSegments

nfg:AllOther


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value0.0010.0651.138.2542037351440.8540.311.0070.7611.0151.5230.8241.0230.9371.5061.8730.4720.549
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.32.96.27.67.949.40.20.10.20.10.20.50.30.20.20.50.50.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.32.96.27.67.949.40.20.10.20.10.20.50.30.20.20.50.50.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:AllOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:CorporateAndIntersegmentEliminations


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value-74.866-76.984-75.139-66.77-62.985-66.474-59.996-59.478-59.308-57.666-55.4640.2240.2010.2310.240.2310.2550.230.2380.2440.224
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-19.0-14.0-17.0-23.2-19.5-13.5-13.5-20.3-16.6-10.4-11.10.00.00.10.10.00.10.10.10.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-19.0-14.0-17.0-23.2-19.5-13.5-13.5-20.3-16.6-10.4-11.10.00.00.10.10.00.10.10.10.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:CorporateAndIntersegmentEliminations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:ExplorationAndProduction


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value22222319112894132158148153158174
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax56.540.643.544.729.326.935.750.643.028.635.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax56.540.643.544.729.326.935.750.643.028.635.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:ExplorationAndProduction100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:Gathering


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value4850473933353435322929
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax12.39.110.713.710.37.27.812.09.25.35.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax12.39.110.713.710.37.27.812.09.25.35.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:Gathering100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:PipelineAndStorage


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value848687807779726968727746435836423530293933
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax21.315.719.927.924.116.116.323.819.313.115.47.89.618.611.17.68.110.87.96.07.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax21.315.719.927.924.116.116.323.819.313.115.47.89.618.611.17.68.110.87.96.07.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:PipelineAndStorage100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:TotalConsolidated


Revenue
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-31
Value404552435289467434
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax102.6100.398.889.695.297.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax102.6100.398.889.695.297.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:TotalConsolidated100.0100.0100.0100.0100.0100.0

nfg:Utility


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value1232691837312625019368132304223
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax31.448.841.625.639.250.943.723.437.155.144.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax31.448.841.625.639.250.943.723.437.155.144.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:Utility100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidatedEntities


Revenue
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value263289467434277351565499
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax91.689.695.297.894.698.5102.4100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax91.689.695.297.894.698.5102.4100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidatedEntities100.0100.0100.0100.0100.0100.0100.0100.0

Revenues

us-gaap:Revenues

us-gaap:Revenues


Revenues
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value394551441287323491444293357552490289342540419286348522422597452313328552432286380660450
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.098.1100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Revenues us-gaap:ConsolidationItems

us-gaap:OperatingSegments


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value394551441287323491444293357552490289342540419286348522422292335449375301339
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.098.1100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

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

us-gaap:IntersegmentElimination, nfg:AllOther


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value0.0020.0010.020.2380.3410.0790.1771.1270.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Revenues0.00.00.00.10.10.00.00.40.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.00.10.10.00.00.40.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:IntersegmentElimination nfg:AllOther0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:IntersegmentElimination, nfg:CorporateAndIntersegmentEliminations


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value-74.949-77.079-75.234-66.884-63.08-66.609-60.131-59.612-59.443-57.721-55.518-52.545-54.435-56.525-47.958-48.31-52.452-56.64-51.84-48.35-50.172-50.513-44.798-41.961-41.574
Percentage of Revenues-19.0-14.0-17.1-23.2-19.5-13.6-13.5-20.3-16.6-10.4-11.3-18.2-15.9-10.5-11.4-16.8-15.1-10.8-12.30.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-19.0-14.0-17.1-23.2-19.5-13.6-13.5-20.3-16.6-10.4-11.1-18.2-15.9-10.5-11.4-16.8-15.1-10.8-12.30.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:IntersegmentElimination nfg:CorporateAndIntersegmentEliminations0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:IntersegmentElimination, nfg:Gathering


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value48494639333534353229292827272324262727232521181816
Percentage of Revenues12.29.010.613.710.37.27.812.09.25.36.19.88.15.15.68.77.75.46.60.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax12.29.010.613.710.37.27.812.09.25.35.99.88.15.15.68.77.75.46.60.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:IntersegmentElimination nfg:Gathering0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:IntersegmentElimination, nfg:PipelineAndStorage


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value26272826262723222223222222232121212222222223222121
Percentage of Revenues6.85.06.59.18.35.65.27.86.44.34.77.86.64.35.27.56.24.35.20.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax6.85.06.59.18.35.65.27.86.44.34.67.86.64.35.27.56.24.35.20.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:IntersegmentElimination nfg:PipelineAndStorage0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:IntersegmentElimination, nfg:TotalReportableSegments


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value74777566626659585957555254564748525651485050444141
Percentage of Revenues19.014.017.023.119.413.513.519.916.610.411.318.215.910.511.416.815.110.812.30.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax19.014.017.023.119.413.513.519.916.610.411.118.215.910.511.416.815.110.812.30.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:IntersegmentElimination nfg:TotalReportableSegments0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:IntersegmentElimination, nfg:Utility


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value0.0740.0970.10.9442.6473.9371.9151.6452.9444.3942.6451.3993.5195.72.1821.7583.3916.0961.8262.3661.7295.3643.6641.8362.614
Percentage of Revenues0.00.00.00.30.80.80.40.60.80.80.50.51.01.10.50.61.01.20.40.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.00.30.80.80.40.60.80.80.50.51.01.10.50.61.01.20.40.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:IntersegmentElimination nfg:Utility0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, nfg:AllOther


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value-0.0010.0641.115.991632341460.8540.311.0070.7771.4961.2321.0960.8620.5380.2180.5540.9781.5080.5610.7060.4460.634
Percentage of Revenues-0.00.00.32.15.06.77.749.90.20.10.20.30.40.20.30.30.20.00.10.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.00.00.32.15.06.77.749.90.20.10.20.30.40.20.30.30.20.00.10.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments nfg:AllOther0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, nfg:CorporateAndIntersegmentEliminations


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value0.0830.0950.0950.1140.0950.1350.1350.1340.1350.0550.0540.0540.1680.2250.2130.2340.2260.2260.2080.2260.2350.2260.2130.2390.217
Percentage of Revenues0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.10.10.10.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.10.10.10.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments nfg:CorporateAndIntersegmentEliminations0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, nfg:ExplorationAndProduction


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value209220191154131155165164158146162143135146139142151159160154156143151163159
Percentage of Revenues53.140.043.453.740.631.737.456.244.526.433.249.539.627.133.249.843.430.638.10.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax53.140.043.453.740.631.737.456.244.526.432.649.539.627.133.249.843.430.638.10.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments nfg:ExplorationAndProduction0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, nfg:Gathering


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value0.5880.6710.3510.0720.00.00.00.0090.00.0020.00.0-0.031-0.0990.170.0290.0340.0260.0260.0710.0650.1130.1250.1360.126
Percentage of Revenues0.10.10.10.00.00.00.00.00.00.00.00.0-0.0-0.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.10.10.00.00.00.00.00.00.00.00.0-0.0-0.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments nfg:Gathering0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, nfg:PipelineAndStorage


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value57595954515148474648545151535350505353535256534847
Percentage of Revenues14.510.813.418.815.810.611.016.112.98.811.118.015.09.912.717.614.410.212.50.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax14.510.813.418.815.810.611.016.112.98.810.918.015.09.912.717.614.410.212.50.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments nfg:PipelineAndStorage0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, nfg:TotalReportableSegments


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value394550439281306458409146356552489288341539418285347521421291333448374300338
Percentage of Revenues100.0100.099.797.994.993.392.350.099.799.999.899.799.599.799.799.699.899.999.80.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.099.797.994.993.392.350.099.799.997.999.799.599.799.799.699.899.999.80.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments nfg:TotalReportableSegments0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, nfg:Utility


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value126270188721242501946712929822075128283187761212571706710621214370110
Percentage of Revenues32.249.142.825.338.551.043.922.936.454.044.926.037.552.544.626.535.049.440.50.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax32.249.142.825.338.551.043.922.936.454.044.026.037.552.544.626.535.049.440.50.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments nfg:Utility0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:Revenues us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:CommodityContract, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value-13.281-3.761-0.312636237.541
Percentage of Revenues-3.4-0.7-0.19.011.44.81.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-3.4-0.7-0.19.011.44.81.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CommodityContract us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.00.00.00.0

us-gaap:Revenues us-gaap:InvestmentType, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:ForeignExchangeContract, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value0.1520.095-0.001-0.237-0.357-0.271-0.191
Percentage of Revenues0.00.0-0.0-0.1-0.1-0.1-0.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.0-0.0-0.1-0.1-0.1-0.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ForeignExchangeContract us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.00.00.00.0

us-gaap:Revenues us-gaap:StatementBusinessSegments

nfg:AllOther


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value0.0010.0651.136.2281633341470.8540.311.0070.7611.0151.5230.8241.0230.9371.5061.8730.4720.549
Percentage of Revenues0.00.00.32.25.16.77.750.30.20.10.20.10.20.50.30.20.20.50.50.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.32.25.16.77.750.30.20.10.20.10.20.50.30.20.20.50.50.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:AllOther100.0100.0100.075.582.588.697.7101.8100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:CorporateAndIntersegmentEliminations


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value-74.866-76.984-75.139-66.77-62.985-66.474-59.996-59.478-59.308-57.666-55.4640.2240.2010.2310.240.2310.2550.230.2380.2440.224
Percentage of Revenues-19.0-14.0-17.0-23.2-19.5-13.5-13.5-20.3-16.6-10.4-11.30.00.00.10.10.00.10.10.10.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-19.0-14.0-17.0-23.2-19.5-13.5-13.5-20.3-16.6-10.4-11.10.00.00.10.10.00.10.10.10.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:CorporateAndIntersegmentEliminations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:ExplorationAndProduction


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value209220191154131155165164158146162168155146138136135130130137120
Percentage of Revenues53.140.043.453.740.631.737.456.244.526.433.228.134.346.842.124.831.445.634.420.826.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax53.140.043.453.740.631.737.456.244.526.432.628.134.346.842.124.831.445.634.420.826.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:ExplorationAndProduction94.098.399.8120.2138.9117.7104.8111.2103.492.493.20.00.00.00.00.00.00.00.00.00.0

nfg:ExplorationandProductionandOtherCategory


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value209220192155132156167166159146163143137147140144151
Percentage of Revenues53.140.043.554.141.031.937.656.744.826.533.449.840.127.333.550.243.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax53.140.043.554.141.031.937.656.744.826.532.849.840.127.333.550.243.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:ExplorationandProductionandOtherCategory0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

nfg:Gathering


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value4850473933353435322929
Percentage of Revenues12.39.110.713.710.37.27.812.09.25.36.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax12.39.110.713.710.37.27.812.09.25.35.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:Gathering100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:PipelineAndStorage


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value848687807779726968727746435836423530293933
Percentage of Revenues21.315.719.927.924.116.116.323.819.313.115.77.89.618.611.17.68.110.87.96.07.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax21.315.719.927.924.116.116.323.819.313.115.47.89.618.611.17.68.110.87.96.07.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:PipelineAndStorage100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:PipelineandStorageandGathering


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value5759595451514847464854515153535050
Percentage of Revenues14.710.913.518.815.810.611.016.112.98.811.118.015.09.912.717.614.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax14.710.913.518.815.810.611.016.112.98.810.918.015.09.912.717.614.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:PipelineandStorageandGathering0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

nfg:TotalConsolidated


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-31
Value394551441323491444
Percentage of Revenues100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:TotalConsolidated97.599.7101.2111.6105.0102.2

nfg:Utility


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value12727018973127254196681323032223032088111729620885146361242
Percentage of Revenues32.249.242.825.739.351.844.323.537.254.845.450.746.126.135.753.748.329.738.454.753.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax32.249.242.825.739.351.844.323.537.254.844.650.746.126.135.753.748.329.738.454.753.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:Utility102.5100.7103.1100.3100.4101.8101.5100.3100.499.599.80.00.00.00.00.00.00.00.00.00.0

nfg:UtilityandEnergyMarketing


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value12627018978139282228791513572729315433922592146
Percentage of Revenues32.249.142.927.143.257.651.327.242.464.755.532.244.962.853.832.242.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax32.249.142.927.143.257.651.327.242.464.754.532.244.962.853.832.242.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:UtilityandEnergyMarketing0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ConsolidatedEntities


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value287323491444293357552490
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.098.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidatedEntities109.2111.6105.0102.2105.8101.697.798.1

Assets

us-gaap:Assets

us-gaap:Assets


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value72087115703969647118670867026462633662786186603659745914579161035867580456615636554158016190670268897227714567396588656762646218634362746108593558365835574752845133518349815105
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:StatementBusinessSegments

nfg:AllOther


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-09-302011-09-302010-09-30
Value3.97127156113123134143122787878787777777676767677767778777676768696959595273209166198
Percentage of Assets0.10.42.21.61.72.02.11.91.21.21.31.31.31.31.31.31.31.31.41.41.41.31.31.21.11.11.11.31.51.51.51.54.33.53.23.9
Percentage of Assets0.10.42.21.61.72.02.11.91.21.21.31.31.31.31.31.31.31.31.41.41.41.31.31.21.11.11.11.31.51.51.51.54.33.53.23.9
Percentage of Assets nfg:AllOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:CorporateAndIntersegmentEliminations


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-09-302011-09-302010-09-30
Value-104.762-181.837-149.596-345.68616916-29.989-65.707-52.855-61.419-42.7023550-9.406-150.93735-50.421-19.719-82.472-63.731-90.662-127.862-75.093-18.077-8.482-90.587-78.047-80.308-88.668-10.672-58.109-10.88331-18.52-15.838131
Percentage of Assets-1.5-2.6-2.1-5.02.40.2-0.4-1.0-0.8-1.0-0.70.60.8-0.2-2.60.6-0.9-0.3-1.5-1.1-1.6-2.2-1.2-0.3-0.1-1.3-1.1-1.2-1.3-0.2-0.9-0.20.5-0.3-0.32.6
Percentage of Assets-1.5-2.6-2.1-5.02.40.2-0.4-1.0-0.8-1.0-0.70.60.8-0.2-2.60.6-0.9-0.3-1.5-1.1-1.6-2.2-1.2-0.3-0.1-1.3-1.1-1.2-1.3-0.2-0.9-0.20.5-0.3-0.32.6
Percentage of Assets nfg:CorporateAndIntersegmentEliminations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:ExplorationAndProduction


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-09-302011-09-302010-09-30
Value206820231875197918862014205919721847177716911568159115401420140713941292126713231436162221032549271832893346310029432821275227462614236718851539
Percentage of Assets28.728.426.628.426.530.030.730.529.228.327.326.026.626.024.523.123.822.322.423.525.928.034.038.039.545.546.846.044.743.043.944.241.239.935.730.2
Percentage of Assets28.728.426.628.426.530.030.730.529.228.327.326.026.626.024.523.123.822.322.423.525.928.034.038.039.545.546.846.044.743.043.944.241.239.935.730.2
Percentage of Assets nfg:ExplorationAndProduction100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:Gathering


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302012-09-302011-09-30
Value84085582394570657655954755555453853353451758958056855355253452048746744749137935232629224722520311640
Percentage of Assets11.712.011.713.69.98.68.38.58.88.88.78.88.98.710.29.59.79.59.89.59.48.47.56.77.15.34.94.84.43.83.63.32.00.8
Percentage of Assets11.712.011.713.69.98.68.38.58.88.88.78.88.98.710.29.59.79.59.89.59.48.47.56.77.15.34.94.84.43.83.63.32.00.8
Percentage of Assets nfg:Gathering100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:PipelineAndStorage


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-09-302011-09-302010-09-30
Value228022402219220421841916192618931894186118601848176317641793192917321718169816801627166415971597153214461400136713041283124412461281124311121080
Percentage of Assets31.631.531.531.730.728.628.729.329.929.730.130.629.529.831.031.629.529.630.029.829.428.725.823.822.220.019.620.319.819.519.920.020.221.021.121.2
Percentage of Assets31.631.531.531.730.728.628.729.329.929.730.130.629.529.831.031.629.529.630.029.829.428.725.823.822.220.019.620.319.819.519.920.020.221.021.121.2
Percentage of Assets nfg:PipelineAndStorage100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:TotalReportableSegments


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-09-302011-09-302010-09-30
Value730972707031719768266557658864056310626161515923584558465865599158415747566756225555585161876642682172417146673365806482622761336039574350704717
Percentage of Assets101.4102.299.9103.395.997.798.399.199.699.799.498.197.898.9101.398.299.699.0100.199.8100.2100.999.999.199.0100.2100.099.999.998.799.498.695.296.895.992.4
Percentage of Assets101.4102.299.9103.395.997.798.399.199.699.799.498.197.898.9101.398.299.699.0100.199.8100.2100.999.999.199.0100.2100.099.999.998.799.498.695.296.895.992.4
Percentage of Assets nfg:TotalReportableSegments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:Utility


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-09-302011-09-302010-09-30
Value211921512113206720482049204319911967201319951921190419631988201320782108207120211904198419301960198920221942186219522019191118702074207020012027
Percentage of Assets29.430.230.029.728.830.530.530.831.032.132.331.831.933.234.333.035.436.336.635.934.434.231.229.228.928.027.227.629.630.830.530.132.734.937.939.7
Percentage of Assets29.430.230.029.728.830.530.530.831.032.132.331.831.933.234.333.035.436.336.635.934.434.231.229.228.928.027.227.629.630.830.530.132.734.937.939.7
Percentage of Assets nfg:Utility100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Liabilities And Stockholders Equity

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:LiabilitiesAndStockholdersEquity


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value72087115703969647118670867026462633662786186603659745914579161035867580456615636554158016190670268897227714567396588656762646218634362746108593558365835574752845133518349815105
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

Assets Current

us-gaap:AssetsCurrent

us-gaap:AssetsCurrent


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value439457453314831496430362403506522544588592521818542556467413361376424513611486452377469626409448429489394355388516589385520620525775
Percentage of AssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets6.16.46.44.511.77.46.45.66.48.18.59.09.910.09.013.49.29.68.37.36.56.56.97.78.96.76.35.67.19.56.57.26.87.86.56.06.78.810.27.310.112.010.615.2

Cash And Cash Equivalents At Carrying Value

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:CashAndCashEquivalentsAtCarryingValue


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302008-09-30
Value1188010920556111342087100109229313227166555285231136129105933611331069433610215023641341126174140192224801841447939545842840440868
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 Assets1.61.11.60.37.81.70.50.31.41.61.83.85.23.92.99.14.94.02.42.31.91.60.61.74.51.00.60.51.62.30.41.02.11.81.01.32.43.33.91.53.62.81.67.70.00.00.00.00.0

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-09-30
Value1198010920563122442794102112233315231170557131
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.71.11.60.37.91.80.70.41.51.61.83.95.33.92.99.12.3

Inventory Raw Materials And Supplies

us-gaap:InventoryRawMaterialsAndSupplies

us-gaap:InventoryRawMaterialsAndSupplies


Inventory
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
Value5352515151484040393734353434353334343433333332303131282725252729313129282828272728313124
Percentage of InventoryRawMaterialsAndSupplies100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.70.70.70.70.70.70.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.50.50.50.40.40.40.40.40.40.50.50.50.50.50.50.50.50.50.60.60.60.5

Other Assets Current

us-gaap:OtherAssetsCurrent

us-gaap:OtherAssetsCurrent


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
Value5156474747100969756576968526047515051495947566660495968544954455646514956484043384458107115
Percentage of OtherAssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.70.80.70.70.71.51.41.50.90.91.11.10.91.00.80.80.90.90.91.10.91.01.10.90.70.81.00.80.70.80.70.90.70.80.80.90.80.70.80.70.91.12.22.3

Property Plant And Equipment Gross

us-gaap:PropertyPlantAndEquipmentGross

us-gaap:PropertyPlantAndEquipmentGross


Property
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
Value12834126481249512351117101155911402112041098810788106041043910254101261002399459816970496209539946094519311926189378691845282457951768974687313710269546791661564386180592256465392601958375637
Percentage of PropertyPlantAndEquipmentGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets178.0177.8177.5177.3164.5172.3170.1173.4173.4171.8171.4172.9171.7171.2173.1163.0167.3167.2169.9169.2170.7162.9150.4138.2129.7120.2118.3122.3120.7117.1119.2117.6112.0110.8111.2111.5110.3105.9103.0106.9105.0116.1117.2110.4

Accumulated Depreciation Depletion And Amortization Property Plant And Equipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value66496572650363536088600357565695563655735520546254115344529452715232518551335085501248794428392934552794259825022413232522422161208820071935187618171750169416461607228522362187
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets92.292.492.491.285.589.585.988.188.988.889.290.590.690.491.486.489.289.390.790.290.584.171.558.650.238.736.437.136.635.435.834.832.932.031.731.631.130.029.531.231.344.144.942.8

Property Plant And Equipment Net

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:PropertyPlantAndEquipmentNet


Property
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
Value61856076599159985621555556465509535252155083497748434782472946744583451944864454444745724882533154815896585357435537536352255151501449464856473946204430422740003784373436013450
Percentage of PropertyPlantAndEquipmentNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets85.885.485.186.179.082.884.285.384.583.182.282.581.180.981.676.678.177.979.279.080.378.878.979.679.681.681.985.284.081.783.482.879.078.879.579.979.275.973.675.773.772.072.367.6

Deferred Tax Assets Liabilities Net

us-gaap:DeferredTaxAssetsLiabilitiesNet

us-gaap:DeferredTaxAssetsLiabilitiesNet


Deferred
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-09-30
Value696653512-891.287-823.795-1137.962-1415.96-1362.844-1313.081-1295.45-1267.648-1222.579-1145.353-1107.439-1055.002-1048.097-1020.508-976.884939-896.26-776.282
Percentage of DeferredTaxAssetsLiabilitiesNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets10.010.18.5-14.6-14.6-17.0-21.0-20.7-20.0-20.7-20.4-19.3-18.3-18.1-17.8-18.0-17.5-17.017.8-17.5-15.2

Operating Lease Right Of Use Asset

us-gaap:OperatingLeaseRightOfUseAsset us-gaap:BalanceSheetLocation

us-gaap:OperatingLeaseRightOfUseAsset

nfg:DeferredCharges


Operating
Period End2020-09-30
Value19
Percentage of OperatingLeaseRightOfUseAsset100.0
Percentage of Assets0.3
Percentage of Assets nfg:DeferredCharges0.0

Other Assets Noncurrent

us-gaap:OtherAssetsNoncurrent

us-gaap:OtherAssetsNoncurrent


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value0.0810.0810.0810.081210.084242420.1020.1080.4260.7540.7420.4790.4850.4910.6040.1160.1570.1620.1670.1720.1780.1841.3550.6330.7380.4592.4472.5240.8430.9651.1052.4182.5942.651.531.6481.7471.8361.983
Percentage of OtherAssetsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.30.00.70.70.70.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Equity Securities Fv Ni

us-gaap:EquitySecuritiesFvNi us-gaap:InvestmentType

us-gaap:EquitySecuritiesFvNi

nfg:EquityMutualFund


Equity
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value343232393731364040383538
Percentage of EquitySecuritiesFvNi100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.50.50.50.60.50.50.50.60.60.60.60.6
Percentage of Assets nfg:EquityMutualFund0.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:EquitySecurities


Equity
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302018-09-30
Value0.9880.8190.6390.6260.5770.9330.8441.8412.776
Percentage of EquitySecuritiesFvNi3.02.51.61.71.82.52.14.67.2
Percentage of Assets0.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:EquitySecurities0.00.00.00.00.00.00.00.00.0

us-gaap:FixedIncomeFunds


Equity
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value707070726463626255545351
Percentage of EquitySecuritiesFvNi202.0212.6217.9182.4173.9197.4169.4153.3136.5139.3150.3133.4
Percentage of Assets1.01.01.01.00.90.90.91.00.90.90.90.9
Percentage of Assets us-gaap:FixedIncomeFunds0.00.00.00.00.00.00.00.00.00.00.00.0

Accounts Payable Current

us-gaap:AccountsPayableCurrent

us-gaap:AccountsPayableCurrent


Accounts
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
Value1131079613494106126132112141127160111127132126981111131088611112618013716812513614515312110577959487889810512695122181145
Percentage of AccountsPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.61.51.41.91.31.61.92.01.82.32.12.71.92.22.32.11.71.92.01.91.61.92.12.72.02.31.82.02.22.31.91.71.21.51.61.51.51.71.82.41.92.43.62.8

Accrued Income Taxes Current

us-gaap:AccruedIncomeTaxesCurrent us-gaap:IncomeTaxAuthority

us-gaap:AccruedIncomeTaxesCurrent

us-gaap:InternalRevenueServiceIRS


Accrued
Period End2020-09-302020-06-302019-09-302018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-30
Value0.1630.1590.00.00.00.08.6881.7752.5739.3550.00.04.1020.05.68613221.6970.00.70930140.0
Percentage of AccruedIncomeTaxesCurrent100.0100.00.00.00.00.0100.0100.0100.0100.00.00.0100.00.0100.0100.0100.0100.00.0100.0100.0100.00.0
Percentage of Assets0.00.00.00.00.00.00.20.00.00.20.00.00.10.00.10.20.30.00.00.00.50.20.0
Percentage of Assets us-gaap:InternalRevenueServiceIRS0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Accrued Liabilities Current

us-gaap:AccruedLiabilitiesCurrent

us-gaap:AccruedLiabilitiesCurrent


Accrued
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302011-09-30
Value16817615414013815017313918019519113238333738343335322424283027293132202525222521264.3867.147
Percentage of AccruedLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.32.52.22.01.92.22.62.22.83.13.12.20.60.60.70.60.60.60.60.60.40.40.50.50.40.40.40.50.30.40.40.40.40.30.40.10.1

Dividends Payable Current

us-gaap:DividendsPayableCurrent

us-gaap:DividendsPayableCurrent


Dividends
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value414040404037373737363636363535353534343434333333333232323231313131300.0303029292929282828
Percentage of DividendsPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.50.50.50.40.50.50.50.50.50.50.50.50.00.50.50.50.50.60.60.50.60.6

Liabilities Current

us-gaap:LiabilitiesCurrent

us-gaap:LiabilitiesCurrent


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value600402906459342583546421395432419440661379365646602325306303276352411446419644570490427513324302269373772734667726420528513603531524
Percentage of LiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets8.35.712.96.64.88.78.26.56.26.96.87.311.16.46.310.610.35.65.45.45.06.16.66.76.18.98.07.36.57.85.24.94.26.012.712.411.412.47.310.010.011.610.710.3

Long Term Debt Current

us-gaap:LongTermDebtCurrent

us-gaap:LongTermDebtCurrent


Long
Period End2020-12-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value5000.00.00.00.00.00.00.00.02500.00.03003000.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.02502502502500.0150150150150200
Percentage of LongTermDebtCurrent100.00.00.00.00.00.00.00.00.0100.00.00.0100.0100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0
Percentage of Assets7.10.00.00.00.00.00.00.00.04.20.00.04.95.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.04.14.24.34.30.02.82.92.93.03.9

us-gaap:LongTermDebtCurrent us-gaap:LongtermDebtType

nfg:FourPointNinePercentNotesDueDecemberOneTwoThousandTwentyOne


Long
Period End2020-12-31
Value500
Percentage of LongTermDebtCurrent100.0
Percentage of Assets7.1
Percentage of Assets nfg:FourPointNinePercentNotesDueDecemberOneTwoThousandTwentyOne0.0

Operating Lease Liability Current

us-gaap:OperatingLeaseLiabilityCurrent us-gaap:BalanceSheetLocation

us-gaap:OperatingLeaseLiabilityCurrent

us-gaap:OtherCurrentLiabilities


Operating
Period End2020-09-30
Value4943000.0
Percentage of OperatingLeaseLiabilityCurrent100.0
Percentage of Assets0.1
Percentage of Assets us-gaap:OtherCurrentLiabilities0.0

Other Accrued Liabilities Current

us-gaap:OtherAccruedLiabilitiesCurrent us-gaap:StatementBusinessSegments

us-gaap:OtherAccruedLiabilitiesCurrent

nfg:AccruedCapitalExpenditures


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-09-30
Value55493433353159336052693837
Percentage of OtherAccruedLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.80.70.50.50.50.50.90.50.90.81.10.60.6
Percentage of Assets nfg:AccruedCapitalExpenditures0.00.00.00.00.00.00.00.00.00.00.00.00.0

nfg:OtherAccruals


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-09-30
Value35343931242128243330473638
Percentage of OtherAccruedLiabilitiesCurrent64.269.1112.094.967.568.547.772.156.058.368.896.2103.5
Percentage of Assets0.50.50.60.50.30.30.40.40.50.50.80.60.6
Percentage of Assets nfg:OtherAccruals0.00.00.00.00.00.00.00.00.00.00.00.00.0

Liabilities Noncurrent

us-gaap:LiabilitiesNoncurrent

us-gaap:LiabilitiesNoncurrent


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value19691986195719031921190918391767166316221588152715491530148216691793174016991719165117401881214621232335232221892170210520402072228822102170209120311993200619651870186417961786
Percentage of LiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets27.327.927.827.327.028.527.427.426.325.825.725.325.925.925.627.430.630.030.030.529.830.030.432.030.832.332.532.533.032.132.633.336.135.235.535.234.834.234.937.236.436.036.135.0

Long Term Debt

us-gaap:LongTermDebt

us-gaap:LongTermDebt


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-302010-09-30
Value262726272630262926282134213421332133213221312131208520852084238320872099209916491649139910491249
Percentage of LongTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets36.536.937.437.836.931.831.833.033.734.034.535.334.935.336.039.135.637.231.324.526.523.619.824.5

Long Term Debt Noncurrent

us-gaap:LongTermDebtNoncurrent

us-gaap:LongTermDebtNoncurrent


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value2627262721302629262821342134213321332132213121311835208520842083178720862099164916491649164916491649164916491649114911491149114913998998998998991049
Percentage of LongTermDebtNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets36.536.930.337.836.931.831.833.033.734.034.535.330.735.336.034.130.537.030.522.823.124.525.025.126.326.526.026.318.819.419.719.724.317.017.517.318.020.5

Deferred Income Tax Liabilities Net

us-gaap:DeferredIncomeTaxLiabilitiesNet

us-gaap:DeferredIncomeTaxLiabilitiesNet


Deferred
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302018-09-30
Value742763735696783777708653647512
Percentage of DeferredIncomeTaxLiabilitiesNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets10.310.710.410.011.011.610.610.110.28.5

Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent us-gaap:RetirementPlanType

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Pension
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value4.8724.5534.9194.9724911
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0
Percentage of Assets0.10.10.10.10.90.2
Percentage of Assets us-gaap:OtherPostretirementBenefitPlansDefinedBenefit0.00.00.00.00.00.0

us-gaap:PensionPlansDefinedBenefit


Pension
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value12212961144227191
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent2510.42837.21243.82898.4460.21665.5
Percentage of Assets1.82.01.02.44.02.9
Percentage of Assets us-gaap:PensionPlansDefinedBenefit0.00.00.00.00.00.0

Operating Lease Liability Noncurrent

us-gaap:OperatingLeaseLiabilityNoncurrent us-gaap:BalanceSheetLocation

us-gaap:OperatingLeaseLiabilityNoncurrent

us-gaap:OtherNoncurrentLiabilities


Operating
Period End2020-09-30
Value14
Percentage of OperatingLeaseLiabilityNoncurrent100.0
Percentage of Assets0.2
Percentage of Assets us-gaap:OtherNoncurrentLiabilities0.0

Lessee Operating Lease Liability Payments Due Year Two

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo


Lessee
Period End2020-09-30
Value3045000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearTwo100.0
Percentage of Assets0.0

Lessee Operating Lease Liability Payments Due Year Three

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree


Lessee
Period End2020-09-30
Value2507000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearThree100.0
Percentage of Assets0.0

Lessee Operating Lease Liability Payments Due Year Four

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour


Lessee
Period End2020-09-30
Value2238000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFour100.0
Percentage of Assets0.0

Lessee Operating Lease Liability Payments Due Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive


Lessee
Period End2020-09-30
Value2086000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFive100.0
Percentage of Assets0.0

Lessee Operating Lease Liability Payments Due After Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive


Lessee
Period End2020-09-30
Value7631000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive100.0
Percentage of Assets0.1

Operating Lease Liability

us-gaap:OperatingLeaseLiability us-gaap:BalanceSheetLocation

us-gaap:OperatingLeaseLiability

nfg:OtherAccrualsAndCurrentLiabilitiesAndOtherDeferredCredits


Operating
Period End2020-09-30
Value19
Percentage of OperatingLeaseLiability100.0
Percentage of Assets0.3
Percentage of Assets nfg:OtherAccrualsAndCurrentLiabilitiesAndOtherDeferredCredits0.0

Lessee Operating Lease Liability Payments Due

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue


Lessee
Period End2020-09-302020-06-302020-03-31
Value222021
Percentage of LesseeOperatingLeaseLiabilityPaymentsDue100.0100.0100.0
Percentage of Assets0.30.30.3

Lessee Operating Lease Liability Undiscounted Excess Amount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount


Lessee
Period End2020-09-30
Value2755000.0
Percentage of LesseeOperatingLeaseLiabilityUndiscountedExcessAmount100.0
Percentage of Assets0.0

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value20112098204419712225207921822139214320902046193719271919185917031684165115681527152716221812202522472599260324102340229922502194213720422016196019891966192118911850181617541745
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets27.929.529.028.331.331.032.633.133.833.333.132.132.332.432.127.928.728.427.727.127.628.029.330.232.636.036.435.835.535.035.935.333.732.533.033.034.133.733.435.836.135.035.234.2

Common Stock Value

us-gaap:CommonStockValue

us-gaap:CommonStockValue


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value9191919090868686868686858585858585858585848484848484848484838383838383838383838282828282
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 Assets1.31.31.31.31.31.31.31.31.41.41.41.41.41.51.51.41.51.51.51.51.51.51.41.31.21.21.21.21.31.31.31.31.31.31.41.41.41.41.41.61.61.61.71.6

Additional Paid In Capital

us-gaap:AdditionalPaidInCapital

us-gaap:AdditionalPaidInCapital


Additional
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value1012100910041004999835831832827821817820816810800796790782775771761756748744746737729716710703695687686676673669666660654650644645643645
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 Assets14.014.214.314.414.012.512.412.913.113.113.213.613.713.713.813.113.513.513.713.713.713.012.111.110.810.210.210.610.810.711.111.110.810.811.011.311.411.311.412.312.612.512.912.6

us-gaap:AdditionalPaidInCapital us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Additional
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-302010-09-302009-09-302008-09-30
Value1012100910041004999835831832827821817820816810800796771744716687669650645602567
Percentage of AdditionalPaidInCapital100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0
Percentage of Assets14.014.214.314.414.012.512.412.913.113.113.213.613.713.713.813.113.711.110.611.111.312.312.60.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Retained Earnings Accumulated Deficit

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:RetainedEarningsAccumulatedDeficit


Retained
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302008-09-30
Value1145110010289911177117613201272126212361172109810971070101485184181776267667369988011031324165016661614158915571493144214261398134313061287127512371206119811801093106310531038985948953
Percentage of RetainedEarningsAccumulatedDeficit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets15.915.514.614.216.517.519.719.719.919.718.918.218.418.117.514.014.314.113.512.012.212.114.216.519.222.823.324.024.123.723.823.222.522.322.022.022.121.921.522.823.322.821.920.80.00.00.00.00.0

us-gaap:RetainedEarningsAccumulatedDeficit us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Retained
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-302010-09-302009-09-302008-09-30
Value11451100102899111771176132012721262123611721098109710701014851676110316141442130612061063948953
Percentage of RetainedEarningsAccumulatedDeficit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets15.915.514.614.216.517.519.719.719.919.718.918.218.418.117.514.012.016.524.023.222.022.820.80.00.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Accumulated Other Comprehensive Income Loss Net Of Tax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value-238.462-101.988-79.741-114.757-41.794-18.917-56.15-52.155-32.666-54.286-28.69-67.75-72.396-47.76-40.919-30.123-33.304-34.091-54.859-5.647.73982989392126122-3.979-43.638-45.055-22.038-19.234-58.609-117.023-84.644-99.02-47.94-51.889-53.13247-75.098-92.521-64.65-44.985
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-3.3-1.4-1.1-1.6-0.6-0.3-0.8-0.8-0.5-0.9-0.5-1.1-1.2-0.8-0.7-0.5-0.6-0.6-1.0-0.10.11.41.61.41.31.81.7-0.1-0.7-0.7-0.4-0.3-0.9-1.9-1.4-1.7-0.8-0.9-0.90.9-1.5-1.8-1.3-0.9

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-30
Value-89.892-89.892-89.892-89.892-86.83-86.83-86.83-86.83-58.848-58.848-46.576-46.576-58.486-58.486-58.486-58.486-76.476-76.476-76.476-76.476-69.794-69.794-69.794-69.794-56.02-56.02-56.02-56.02-56.293-56.293-56.293-56.293
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax37.788.1112.778.3207.8459.0154.6166.5180.2108.4162.368.780.8122.5142.9194.2229.6224.3139.41356.0-901.8-84.9-70.9-74.7-60.7-44.2-45.71407.9129.0124.9255.4292.7
Percentage of Assets-1.2-1.3-1.3-1.3-1.2-1.3-1.3-1.3-0.9-0.9-0.8-0.8-1.0-1.0-1.0-1.0-1.3-1.3-1.4-1.4-1.3-1.2-1.1-1.0-0.8-0.8-0.8-0.8-0.9-0.9-0.9-0.9
Percentage of Assets us-gaap:AccumulatedDefinedBenefitPlansAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-30
Value-148.57-12.09610-24.86545673034
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax62.311.9-12.721.7-107.8-359.0-54.6-66.5
Percentage of Assets-2.1-0.20.1-0.40.61.00.50.5
Percentage of Assets us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.00.00.00.00.0

us-gaap:AccumulatedOtherComprehensiveIncome


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-302010-09-302009-09-302008-09-30
Value-238.462-101.988-79.741-114.757-41.794-18.917-56.15-52.155-32.666-54.286-28.69-67.75-72.396-47.76-40.919-30.123-5.6493-3.979-19.234-99.02-47.699-44.985-42.3962.963
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0-100.0100.00.00.0
Percentage of Assets-3.3-1.4-1.1-1.6-0.6-0.3-0.8-0.8-0.5-0.9-0.5-1.1-1.2-0.8-0.7-0.5-0.11.4-0.1-0.3-1.7-0.9-0.90.00.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Stock Issued During Period Value New Issues

us-gaap:StockIssuedDuringPeriodValueNewIssues us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodValueNewIssues

us-gaap:AdditionalPaidInCapital


Stock
Period End2020-09-302020-06-30
Value-0.089161
Percentage of StockIssuedDuringPeriodValueNewIssues100.0100.0
Percentage of Assets0.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.0

us-gaap:CommonStock


Stock
Period End2020-09-302020-06-30
Value0.04.37
Percentage of StockIssuedDuringPeriodValueNewIssues-0.02.7
Percentage of Assets0.00.0
Percentage of Assets us-gaap:CommonStock0.00.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value25421220411623222316712322923610422022014511920225979141193255873914021068
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax64.638.546.440.672.145.537.842.264.342.820.90.036.932.238.261.547.018.349.350.738.719.40.00.00.00.0

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value-174780000.0-155320000.0-66870000.0-649690000.0-182610000.0-198040000.0-193280000.0-208660000.0-201320000.0-209080000.0-180120000.0-174100000.0-176670000.0-166510000.0-258180000.0-277770000.0-266760000.0-233640000.0-259810000.0-121780000.0-143970000.0-192100000.0-74459000.0-97141000.0-168190000.0-62452000.0
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-44.3-28.2-15.2-225.6-56.5-40.3-43.5-71.1-56.4-37.8-36.10.0-29.6-36.8-82.4-84.5-48.3-54.0-90.8-32.0-21.8-42.60.00.00.00.0

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value-40.642-86.016-49.001-10.673391524217-36.678-37.296-44.765-24.1077.1697.0777224-24.92829814-31.34-48.636-210.92-29.019-11.378-20.402-9.533
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-10.3-15.6-11.1-3.7121.110.79.76.0-10.3-6.7-9.00.01.21.623.07.4-4.569.05.1-8.2-7.4-46.80.00.00.00.0

Deferred Income Tax Expense Benefit

us-gaap:DeferredIncomeTaxExpenseBenefit us-gaap:ImpairedLongLivedAssetsHeldAndUsedByType

us-gaap:DeferredIncomeTaxExpenseBenefit

nfg:ImpairmentofOilandGasProducingProperties


Deferred
Period End2020-12-312020-09-302020-06-302016-06-302016-03-312015-06-30
Value21695.034166248
Percentage of DeferredIncomeTaxExpenseBenefit100.0100.0100.0100.0100.0100.0

Depreciation Depletion And Amortization

us-gaap:DepreciationDepletionAndAmortization

us-gaap:DepreciationDepletionAndAmortization


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value848483807377747471656463606155555556565658637070798210210396899386888072717463625557605349504644
Percentage of DepreciationDepletionAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Increase Decrease In Inventories

us-gaap:IncreaseDecreaseInInventories

us-gaap:IncreaseDecreaseInInventories


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value8.234-13.385-13.873188.489-13.101-6.9852111-20.74-8.353229.172-17.667-10.337178.777-13.879-10.597196.954-19.171-3.466168.826-19.699-9.3862217-34.684-17.977277.84-28.45-3.941256.303-39.3822.226327.757-35.9725.8281317-35.093-2.839
Percentage of IncreaseDecreaseInInventories100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value25421220411623222316712322923610422022014511920225979141193255873914021068
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax64.638.546.440.672.145.537.842.264.342.820.90.036.932.238.261.547.018.349.350.738.719.40.00.00.00.0

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value8611277-145.54541-106.0688647639010237639119845598988378.286-147.687-189.109-187.703-293.134168457649582475885674843676037461155838428064
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax21.920.417.6-50.512.8-21.619.516.117.816.420.513.118.417.047.315.917.117.121.00.00.00.00.00.00.00.00.00.00.00.00.00.00.014.315.015.613.112.214.013.112.317.513.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value-9.512-2.656-0.2256.00226185.3216.372.756-3.411-7.286-11.55-2.563-2.6487.6234.761106.0581819333539262931142.251-6.211-15.475.884
Percentage of NetIncomeLoss-11.0-2.4-0.3-4.164.1-17.26.113.54.3-3.8-7.1-30.4-4.1-2.93.810.418.06.820.552.9408.6-24.3-20.7-14.2-9.9187.316.73.9-9.6-16.27.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2.4-0.5-0.12.18.23.71.22.20.8-0.6-1.5-4.0-0.7-0.51.81.73.11.24.30.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:StatementBusinessSegments

nfg:AllOther


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value1.039-0.98337-1.801-0.0091.1690.371-2.063-0.003-0.1280.3840.1020.2970.207-0.7190.156-0.098-0.221-0.1790.1830.43-0.0230.189-0.068-0.0280.098-0.0060.1820.0240.2780.675-8.5554.4993.0641.885-5.5442.8151.3391.404-0.6912.71332-0.574
Percentage of NetIncomeLoss1.2-0.948.31.2-0.0-1.10.4-4.4-0.0-0.10.40.30.50.2-0.40.3-0.2-0.2-0.20.55.20.0-0.10.00.00.6-0.00.30.00.30.8-17.97.73.62.8-11.46.52.02.3-1.85.827.8-1.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.3-0.28.5-0.6-0.00.20.1-0.7-0.0-0.00.10.00.10.0-0.20.1-0.0-0.0-0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.50.4-1.80.90.20.3-0.20.74.9-0.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:AllOther103900.0-1512.33323.9-21.8-0.03.11.1-1.4-0.4-41.338.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0402.6185.7-364.0341.6130.9149.8-45.9144.86818.0-104.6

nfg:CorporateAndIntersegmentEliminations


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value-0.795-1.0752.067-1.1993.577-5.4461.611-1.6030.8932.278-0.57-3.681-1.118-3.329-13.226-2.947-0.233-0.2910.701-3.174-1.3641.4651.762-3.444-1.193-1.260.205-6.182-0.0042.537-0.624-1.142-0.406-0.65-0.927-5.056-0.192-0.565-0.761-5.546-1.328-0.204-0.756
Percentage of NetIncomeLoss-0.9-1.02.70.88.75.11.9-3.41.42.5-0.6-9.7-1.8-3.6-6.7-6.5-0.4-0.30.8-8.5-16.5-1.0-0.91.80.4-7.60.2-10.8-0.02.7-0.8-2.4-0.7-0.8-1.4-10.4-0.4-0.8-1.3-14.8-2.8-0.2-1.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.2-0.20.5-0.41.1-1.10.4-0.50.20.4-0.1-1.3-0.3-0.6-3.2-1.0-0.1-0.10.20.00.00.00.00.00.00.00.00.00.00.00.00.00.0-0.1-0.2-1.6-0.1-0.1-0.2-1.9-0.3-0.0-0.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:CorporateAndIntersegmentEliminations1.11.4-2.81.8-5.78.2-2.72.7-1.5-4.01.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0-290.2-461.2-2188.7-80.0-244.6-298.4-2411.3-558.0-83.6-337.5

nfg:ExplorationAndProduction


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value3936-29.623-169.171-6.434-175.27523252621381927261063030333516-19.165-213.335-237.086-207.019-323.113-53.5622633322431293127262221223030323327
Percentage of NetIncomeLoss45.132.7-38.1116.2-15.6165.227.753.341.624.137.251.544.128.953.766.650.437.839.544.6-231.3144.5125.4110.3110.2-321.331.558.650.225.637.861.254.332.339.345.250.732.949.982.369.928.846.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax9.96.7-6.7-58.7-2.0-35.75.48.67.44.07.66.88.14.925.410.68.66.58.30.00.00.00.00.00.00.00.00.00.00.00.00.00.04.65.97.06.74.07.010.78.65.06.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:ExplorationAndProduction17.516.4-15.5-131.4-6.8-132.615.117.017.313.821.90.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

nfg:Gathering


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value2020201715191516141214141111459.0041010108.5379.4737.5684.9217.5956.2266.40511108.7177.3246.1473.8794.4073.0931.942
Percentage of NetIncomeLoss23.618.426.4-12.136.9-18.818.435.723.014.013.838.918.412.822.919.816.911.512.422.7114.3-5.1-2.6-4.0-2.138.413.718.313.57.77.58.17.53.62.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax5.23.84.76.14.74.13.65.84.12.32.85.13.42.210.83.12.92.02.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.50.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:Gathering42.041.243.744.445.856.445.848.144.543.247.80.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

nfg:PipelineAndStorage


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value21242416222218151517251520223813161919161721211817232019172119151416162512129.9597.4794.503108.578
Percentage of NetIncomeLoss25.422.231.1-11.054.8-20.820.932.524.819.624.540.432.924.719.430.326.821.621.844.8209.1-14.4-11.3-9.8-6.0140.224.533.327.822.423.332.324.119.624.951.429.219.116.420.09.69.514.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax5.64.55.55.67.04.54.15.24.43.25.05.36.04.29.24.84.63.74.60.00.00.00.00.00.00.00.00.00.00.00.00.00.02.83.78.03.82.32.32.61.21.71.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:PipelineAndStorage26.128.827.620.029.127.925.122.022.924.532.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.036.239.043.034.530.528.324.215.027.625.6

nfg:TotalReportableSegments


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value8611438-142.54537-101.7918450628810241639421248608988409.22-149.129-191.06-184.191-291.913178463649282575483665940666043458359
Percentage of NetIncomeLoss99.7101.849.097.991.496.097.7107.898.697.6100.2109.4101.3103.4107.0106.1100.6100.699.4108.0111.3101.0101.098.199.6107.099.8110.4100.097.099.9120.393.097.298.6121.793.998.998.9116.797.072.3102.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax21.920.88.6-49.511.7-20.719.017.417.616.020.614.418.617.650.716.917.217.220.90.00.00.00.00.00.00.00.00.00.00.00.00.00.013.914.819.012.312.113.915.211.912.713.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:TotalReportableSegments0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

nfg:Utility


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value4.8413223-6.9696.2543126-7.7297.3623525-7.0663.933320-4.1684.3482521-1.7852.1793118-3.2875.7273822-0.5274.82635240.6627.6334225.8655.09628190.8296.3283322
Percentage of NetIncomeLoss5.628.529.64.815.2-29.730.7-16.311.539.325.0-18.66.236.310.6-9.17.328.723.8-4.826.3-21.6-9.81.8-2.0229.426.7-0.97.537.329.41.413.040.333.712.011.842.031.92.213.528.639.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.25.85.2-2.41.96.46.0-2.62.16.45.1-2.41.16.25.0-1.51.24.95.00.00.00.00.00.00.00.00.00.00.00.00.00.00.05.85.11.91.55.14.50.31.75.05.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax nfg:Utility3.911.912.6-9.54.912.613.7-11.35.611.711.50.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value8611277-145.54541-106.06886476390102376391198
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax21.920.417.6-50.512.8-21.619.516.117.816.420.513.118.417.047.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Share Based Compensation

us-gaap:ShareBasedCompensation

us-gaap:ShareBasedCompensation


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value3.6394.7243.9335.2152.1364.3143.2665.0425.4135.425.3113.9923.9083.9573.9053.4053.2253.152.4822.6170.621.5580.96-5.1752.3982.9073.078-0.6754.3935.0852.962.743.113.2943.302
Percentage of ShareBasedCompensation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value-174780000.0-155320000.0-66870000.0-649690000.0-182610000.0-198040000.0-193280000.0-208660000.0-201320000.0-209080000.0-180120000.0-174100000.0-176670000.0-166510000.0-258180000.0-277770000.0-266760000.0-233640000.0-259810000.0-121780000.0-143970000.0-192100000.0-74459000.0-97141000.0-168190000.0-62452000.0
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-44.3-28.2-15.2-225.6-56.5-40.3-43.5-71.1-56.4-37.8-36.10.0-29.6-36.8-82.4-84.5-48.3-54.0-90.8-32.0-21.8-42.60.00.00.00.0

Payments To Acquire Property Plant And Equipment

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value173155183165155196198201200209177180142119142135106102106991221721862992252482443042421721941901731761622592772662322531912001921289616862
Percentage of PaymentsToAcquirePropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value-40.642-86.016-49.001-10.673391524217-36.678-37.296-44.765-24.1077.1697.0777224-24.92829814-31.34-48.636-210.92-29.019-11.378-20.402-9.533
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-10.3-15.6-11.1-3.7121.110.79.76.0-10.3-6.7-9.00.01.21.623.07.4-4.569.05.1-8.2-7.4-46.80.00.00.00.0

Proceeds From Issuance Of Long Term Debt

us-gaap:ProceedsFromIssuanceOfLongTermDebt

us-gaap:ProceedsFromIssuanceOfLongTermDebt


Proceeds
Period End2021-06-302020-09-302019-09-302016-09-302015-09-302014-09-302014-06-302013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value0.0-0.1010.00.0-1.0270.00.00.00.04950.00.00.00.04960.00.00.00.0
Percentage of ProceedsFromIssuanceOfLongTermDebt0.0100.00.00.0100.00.00.00.00.0100.00.00.00.00.0100.00.00.00.00.0

us-gaap:ProceedsFromIssuanceOfLongTermDebt us-gaap:LongtermDebtType

nfg:TwoPointNineFivePercentNotesDueMarchFirstTwoThousandThirtyOne


Proceeds
Period End2021-02-24
Value495
Percentage of ProceedsFromIssuanceOfLongTermDebt0.0

Repayments Of Long Term Debt

us-gaap:RepaymentsOfLongTermDebt

us-gaap:RepaymentsOfLongTermDebt


Repayments
Period End2021-06-302019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312014-09-302014-06-302013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value0.00.00.00.00.02590.00.03070.00.00.00.00.00.00.00.02500.00.00.00.01500.00.00.02000.0
Percentage of RepaymentsOfLongTermDebt0.00.00.00.00.0100.00.00.0100.00.00.00.00.00.00.00.00.0100.00.00.00.00.0100.00.00.00.0100.00.0

Payments Of Dividends Common Stock

us-gaap:PaymentsOfDividendsCommonStock

us-gaap:PaymentsOfDividendsCommonStock


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value4040404037373737363636363535353534343434333333333232323231313131300.060302929292928282828272726
Percentage of PaymentsOfDividendsCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Debt Instrument Interest Rate Stated Percentage

us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:LongtermDebtType

us-gaap:DebtInstrumentInterestRateStatedPercentage

nfg:FourPointNinePercentNotesDueDecemberFirstTwoThousandTwentyOne


Debt
Period End2020-09-30
Value4.9
Percentage of DebtInstrumentInterestRateStatedPercentage100.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations nfg:FourPointNinePercentNotesDueDecemberFirstTwoThousandTwentyOne0.0

nfg:SevenPointFourPercentDueMarchTwoThousandTwentyThreeToJuneTwoThousandTwentyFive


Debt
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value7.40.0740.0740.0740.0740.074
Percentage of DebtInstrumentInterestRateStatedPercentage151.00.00.00.00.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.00.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations nfg:SevenPointFourPercentDueMarchTwoThousandTwentyThreeToJuneTwoThousandTwentyFive0.00.00.00.00.00.0

nfg:TwoPointNineFivePercentNotesDueMarchFirstTwoThousandThirtyOne


Debt
Period End2021-02-24
Value2.95
Percentage of DebtInstrumentInterestRateStatedPercentage0.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations nfg:TwoPointNineFivePercentNotesDueMarchFirstTwoThousandThirtyOne0.0

Deferred Tax Liabilities

us-gaap:DeferredTaxLiabilities

us-gaap:DeferredTaxLiabilities


Deferred
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-09-30
Value952971860129713061602181517631729171317031774170416571613150214621397134912581091
Percentage of DeferredTaxLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Deferred Tax Assets Net

us-gaap:DeferredTaxAssetsNet

us-gaap:DeferredTaxAssetsNet


Deferred
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-09-30
Value255318347406482464399400415417435551559550558454441420409362315
Percentage of DeferredTaxAssetsNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Deferred Tax Assets Valuation Allowance

us-gaap:DeferredTaxAssetsValuationAllowance

us-gaap:DeferredTaxAssetsValuationAllowance


Deferred
Period End2021-06-302021-03-312020-12-312020-09-302020-03-312019-09-302018-09-302017-09-30
Value64636363560.05.00.0
Percentage of DeferredTaxAssetsValuationAllowance100.0100.0100.0100.0100.00.0100.00.0

Proceeds From Repayments Of Short Term Debt

us-gaap:ProceedsFromRepaymentsOfShortTermDebt

us-gaap:ProceedsFromRepaymentsOfShortTermDebt


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value0.0-25.0-5.030-230.09084550.00.00.00.00.00.0-31.4310.0-157.5-15.487850.00.00.00.00.0-238.067100500.0-20.0400.0-20.5200.0
Percentage of ProceedsFromRepaymentsOfShortTermDebt0.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.0100.0100.00.0100.0100.0100.0100.00.00.00.00.00.0100.0100.0100.0100.00.0100.0100.00.0100.0100.00.0

dei:EntityListingParValuePerShare

dei:EntityListingParValuePerShare


Entity
Period End2021-06-302021-03-312020-12-31
Value001.0
Percentage of EntityListingParValuePerShare0.00.0100.0

nfg:AcquisitionOfUpstreamAssetsAndMidstreamGatheringAssets

nfg:AcquisitionOfUpstreamAssetsAndMidstreamGatheringAssets


Acquisition
Period End2020-09-30
Value479
Percentage of AcquisitionOfUpstreamAssetsAndMidstreamGatheringAssets100.0

nfg:AlternativeRevenuePrograms us-gaap:StatementBusinessSegments

nfg:AlternativeRevenuePrograms

nfg:TotalConsolidated


Alternative
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-31
Value3.061.8785.5940.4924.4222.86
Percentage of AlternativeRevenuePrograms100.0100.0100.0100.0100.0100.0

nfg:Utility


Alternative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value3.061.8785.5940.2140.4924.4222.860.2240.465-1.466-0.528
Percentage of AlternativeRevenuePrograms100.0100.0100.00.0100.0100.0100.00.00.00.00.0

us-gaap:ConsolidatedEntities


Alternative
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0.2140.4924.4222.860.2240.465-1.466-0.528
Percentage of AlternativeRevenuePrograms0.0100.0100.0100.00.00.00.00.0

nfg:BeginningRetainedEarningsUnappropriatedAndCurrentPeriodNetIncomeLoss

nfg:BeginningRetainedEarningsUnappropriatedAndCurrentPeriodNetIncomeLoss


Beginning
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value118711411069-145.54512181214135947130012621201371133110610504587785176537707732914-187.7031357168316995716211588152447145714291374481318130412663712271209112138108110661012
Percentage of BeginningRetainedEarningsUnappropriatedAndCurrentPeriodNetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonthsAfterTax

nfg:CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonthsAfterTax


Cash
Period End2021-06-302021-03-312020-12-31
Value-100.3-22.32.4
Percentage of CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonthsAfterTax100.0100.0100.0

nfg:CumulativeEffectofAdoptionofAuthoritativeGuidanceforHedging

nfg:CumulativeEffectofAdoptionofAuthoritativeGuidanceforHedging


Cumulative
Period End2020-09-302020-06-302020-03-312019-12-31
Value000950000.0
Percentage of CumulativeEffectofAdoptionofAuthoritativeGuidanceforHedging0.00.00.0100.0

nfg:CumulativeEffectofAdoptionofAuthoritativeGuidanceforHedging us-gaap:StatementEquityComponents

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Cumulative
Period End2020-09-302020-06-302020-03-312019-12-31
Value000950000.0
Percentage of CumulativeEffectofAdoptionofAuthoritativeGuidanceforHedging0.00.00.0100.0

nfg:ImpairmentOfOilAndGasProducingPropertiesAfterTax

nfg:ImpairmentOfOilAndGasProducingPropertiesAfterTax


Impairment
Period End2020-09-302020-06-302020-03-31
Value18313129
Percentage of ImpairmentOfOilAndGasProducingPropertiesAfterTax100.0100.0100.0

nfg:ImpairmentofOilandGasProducingProperties

nfg:ImpairmentofOilandGasProducingProperties


Impairmentof
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-06-302019-03-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value0.00.076253181770.00.00.00.00.00.032823974354175881200.00.00.00.0
Percentage of ImpairmentofOilandGasProducingProperties0.00.0100.0100.0100.0100.00.00.00.00.00.00.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0

nfg:IncreaseDecreaseInCustomerAdvancesCurrent

nfg:IncreaseDecreaseInCustomerAdvancesCurrent


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value0-16032000.0713000.014758000.0-54000.0-13112000.0683000.012878000.0-267000.0-6918000.0-6258000.013412000.043000.0-18244000.02697000.0
Percentage of IncreaseDecreaseInCustomerAdvancesCurrent0.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:NetAmortizationAndDeferralForRegulatoryPurposesIncludingVolumetricAdjustments us-gaap:RetirementPlanType

nfg:NetAmortizationAndDeferralForRegulatoryPurposesIncludingVolumetricAdjustments

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value6.6399.4516.8544.4656.0368.8466.2492.1873.7576.5653.9711.7853.3866.253.608-0.2961.3023.791.3122.4663.936
Percentage of NetAmortizationAndDeferralForRegulatoryPurposesIncludingVolumetricAdjustments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value2.7727.713.713-2.2920.6045.5191.527-2.997-0.1134.7860.8190.1010.7126.4921.721-3.108-3.1936.2340.535-3.5740.014
Percentage of NetAmortizationAndDeferralForRegulatoryPurposesIncludingVolumetricAdjustments41.881.654.2-51.310.062.424.4-137.0-3.072.920.65.721.0103.947.71050.0-245.2164.540.8-144.90.4

nfg:NetProceedsFromSaleOfTimberProperties

nfg:NetProceedsFromSaleOfTimberProperties


Net
Period End2021-06-302021-03-312020-12-31
Value0.00.0104
Percentage of NetProceedsFromSaleOfTimberProperties0.00.0100.0

nfg:OtherComprehensiveIncomeLossCumulativeEffectofAdoptionofAuthoritativeGuidanceforHedging

nfg:OtherComprehensiveIncomeLossCumulativeEffectofAdoptionofAuthoritativeGuidanceforHedging


Other
Period End2020-09-302020-06-302020-03-312019-12-312019-06-302019-03-312018-12-31
Value0001313000.0000
Percentage of OtherComprehensiveIncomeLossCumulativeEffectofAdoptionofAuthoritativeGuidanceforHedging0.00.00.0100.00.00.00.0

nfg:OtherComprehensiveIncomeLossCumulativeEffectofAdoptionofAuthoritativeGuidanceforHedgingTax

nfg:OtherComprehensiveIncomeLossCumulativeEffectofAdoptionofAuthoritativeGuidanceforHedgingTax


Other
Period End2020-09-302020-06-302020-03-312019-12-312019-06-302019-03-312018-12-31
Value000363000.0000
Percentage of OtherComprehensiveIncomeLossCumulativeEffectofAdoptionofAuthoritativeGuidanceforHedgingTax0.00.00.0100.00.00.00.0

nfg:ProposedRefundToCustomersFromOverCollectionOfOPEBExpenses us-gaap:StatementGeographical

nfg:ProposedRefundToCustomersFromOverCollectionOfOPEBExpenses

stpr:PA


Proposed
Period End2021-06-30
Value50
Percentage of ProposedRefundToCustomersFromOverCollectionOfOPEBExpenses100.0

us-gaap:AccountsReceivablePurchase

us-gaap:AccountsReceivablePurchase


Accounts
Period End2021-06-302021-03-312020-12-31
Value1096300.0567.0170.0
Percentage of AccountsReceivablePurchase100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivableWriteOffs

us-gaap:AllowanceForDoubtfulAccountsReceivableWriteOffs


Allowance
Period End2021-06-302021-03-312020-12-31
Value4955500.03055.01438.0
Percentage of AllowanceForDoubtfulAccountsReceivableWriteOffs100.0100.0100.0

us-gaap:CapitalExpendituresIncurredButNotYetPaid

us-gaap:CapitalExpendituresIncurredButNotYetPaid


Capital
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value13155229-1.356-34.348931.6964.496-11.246861719-4.177562410-12.0334816-21.678-27.92593-3.62828-7.181010.88126565222-18.461-9.05186-45.843-51.15-5.411545.6
Percentage of CapitalExpendituresIncurredButNotYetPaid100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortization

us-gaap:CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortization


Capitalized
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-12.514134146.41657-64.14176.458-85.16528-9.577-93.601-13.7-12.4126-72.624-32.5-6.1169-89.76628-13.4162-67.359-33.154130-106.918-8.2-3.6155-89.523-127.448226226
Percentage of CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect


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
Value39-28.94688-543.4224417717-67.09-8.276-9.912-120.509-82.5438360-386.517
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths

us-gaap:CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths


Cash
Period End2021-06-302021-03-312020-12-31
Value-138.1-31.53.3
Percentage of CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths100.0100.0100.0

us-gaap:CommonStockDividendsPerShareDeclared

us-gaap:CommonStockDividendsPerShareDeclared


Common
Period End2021-06-302020-06-302020-03-312019-12-312019-06-302019-03-312018-12-312018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value0.4550.4450.4350.4350.4350.4250.4250.4250.4150.4150.4150.4150.4050.4050.4050.4050.3950.3950.3950.3950.3850.3850.3850.3850.3750.3750.3750.3750.3650.3650.3650.3650.3550.3550.3550.3550.3450.3450.3450.3450.3350.335
Percentage of CommonStockDividendsPerShareDeclared100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredIncomeTaxesAndTaxCredits

us-gaap:DeferredIncomeTaxesAndTaxCredits


Deferred
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value273426-62.01911535111202664251832-94.676124118442214-143.899-140.013-159.471-208.467-22.856332347413026386141392342392333693670222021
Percentage of DeferredIncomeTaxesAndTaxCredits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value-0.212-0.212-0.212-0.134-0.134-0.134-0.134-1.491-1.49-1.49-1.49-2.64-2.639-2.639-2.639-4.604-4.604-4.604-4.604-1.383-1.382
Percentage of DefinedBenefitPlanAmortizationOfGainsLosses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value-9.203-9.203-9.203-9.846-9.846-9.846-9.846-8.024-8.024-8.024-8.024-9.301-9.301-9.301-9.301-10.672-10.672-10.672-10.672-8.062-8.062
Percentage of DefinedBenefitPlanAmortizationOfGainsLosses4341.04341.04341.07347.87347.87347.87347.8538.2538.5538.5538.5352.3352.4352.4352.4231.8231.8231.8231.8582.9583.4

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value-107000.0-107000.0-107000.0-107000.0-107000.0-107000.0-107000.0-108000.0-107000.0-107000.0-107000.0-107000.0-107000.0-107000.0-107000.0-107000.0-107000.0-107000.0-107000.0-228000.0-228000.0
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value158000.0158000.0158000.0182000.0182000.0182000.0182000.0207000.0206000.0206000.0206000.0235000.0235000.0235000.0235000.0265000.0264000.0264000.0264000.0309000.0308000.0
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit-147.7-147.7-147.7-170.1-170.1-170.1-170.1-191.7-192.5-192.5-192.5-219.6-219.6-219.6-219.6-247.7-246.7-246.7-246.7-135.5-135.1

us-gaap:DefinedBenefitPlanContributionsByEmployer us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanContributionsByEmployer

nfg:VebaTrusts


Defined
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
Value0.61.40.70.10.61.40.70.10.61.40.70.10.61.40.7
Percentage of DefinedBenefitPlanContributionsByEmployer100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
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
Value4.39.45.21.1214.2117.80.0150.00.0295.380.00.0272.046
Percentage of DefinedBenefitPlanContributionsByEmployer716.7671.4742.91121.0700.0821.41114.315.00.00.04171.45380.00.00.03942.90.0

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value7.2417.2417.2417.3087.3087.3087.3087.5397.5397.5397.5397.877.8717.8717.8717.8647.8657.8657.8657.8847.883
Percentage of DefinedBenefitPlanExpectedReturnOnPlanAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value141414151515151515151515151515141414141414
Percentage of DefinedBenefitPlanExpectedReturnOnPlanAssets200.8200.8200.8205.5205.5205.5205.5206.8206.8206.8206.8196.0196.0196.0196.0189.9189.8189.8189.8188.3188.3

us-gaap:DefinedBenefitPlanInterestCost us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanInterestCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value2.3262.3262.3263.2283.2283.2283.2284.2874.2864.2864.2863.73.73.73.74.7514.7524.7524.7525.0975.096
Percentage of DefinedBenefitPlanInterestCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value5.4225.4225.4227.4827.4837.4837.4839.5959.5949.5949.5948.2528.2528.2528.2529.5959.5969.5969.5961010
Percentage of DefinedBenefitPlanInterestCost233.1233.1233.1231.8231.8231.8231.8223.8223.8223.8223.8223.0223.0223.0223.0202.0201.9201.9201.9207.6207.6

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value2.2295.0412.4440.8152.3855.1952.5980.6972.2675.0752.4810.6052.2055.0692.4271.73.2985.7863.3081.4172.886
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value5.484106.4252.5325.429106.3521.3564.249.1395.1724.945.551116.565.4865.402149.133.4617.049
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost246.0206.7262.9310.7227.6199.1244.5194.5187.0180.1208.5816.5251.7223.5270.3322.7163.8256.3276.0244.2244.2

us-gaap:DefinedBenefitPlanServiceCost us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanServiceCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value0.40.40.40.4030.4020.4020.4020.3790.380.380.380.4570.4580.4580.4580.6120.6120.6120.6120.5830.583
Percentage of DefinedBenefitPlanServiceCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value2.4662.4662.4662.3292.332.332.332.122.122.122.122.482.482.482.482.9922.9922.9922.9922.9272.928
Percentage of DefinedBenefitPlanServiceCost616.5616.5616.5577.9579.6579.6579.6559.4557.9557.9557.9542.7541.5541.5541.5488.9488.9488.9488.9502.1502.2

us-gaap:DerivativeGainLossOnDerivativeNet us-gaap:StatementBusinessSegments

us-gaap:DerivativeGainLossOnDerivativeNet

nfg:AllOther


Derivative
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value-2.026-3.537-4.251-0.8162.6580.00.00.0
Percentage of DerivativeGainLossOnDerivativeNet100.0100.0100.0100.0100.00.00.00.0

nfg:ExplorationAndProduction


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value-13.281-3.761-0.312636237.541165.194-12.064-11.947
Percentage of DerivativeGainLossOnDerivativeNet0.00.00.0-1284.7-1038.3-550.4-924.1622.50.00.00.0

nfg:TotalConsolidated


Derivative
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-31
Value-13.281-3.761-0.3133196.725
Percentage of DerivativeGainLossOnDerivativeNet0.00.00.0-938.3-450.4-824.1

us-gaap:ConsolidatedEntities


Derivative
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value2433196.725154.993-11.527-8.822
Percentage of DerivativeGainLossOnDerivativeNet-1184.7-938.3-450.4-824.1592.20.00.00.0

us-gaap:DividendsCommonStockCash

us-gaap:DividendsCommonStockCash


Dividends
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value4140404040373737373636363635353535343434343333333332323232313131313030303029292929282828282727
Percentage of DividendsCommonStockCash100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DividendsCommonStockCash us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Dividends
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value414040404037373737363636363535
Percentage of DividendsCommonStockCash100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectOnFutureCashFlowsAmount

us-gaap:EffectOnFutureCashFlowsAmount


Effect
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312016-06-302016-03-312015-12-312015-06-302015-03-31
Value911271831253226225225316897
Percentage of EffectOnFutureCashFlowsAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:GainLossOnSaleOfTimberProperty

us-gaap:GainLossOnSaleOfTimberProperty


Gain
Period End2021-06-302021-03-312020-12-31
Value0.00.051
Percentage of GainLossOnSaleOfTimberProperty0.00.0100.0

us-gaap:IncreaseDecreaseInAccountsPayableTrade

us-gaap:IncreaseDecreaseInAccountsPayableTrade


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value-1.1399.154-0.5418.509-7.701-13.7458.28-8.638-26.3588.7241.50215-8.511-2.3351312-8.951-4.8081813-21.901-11.002-20.78423-51.6794319-11.237-42.9932939-2.938-9.215146.16323-9.934-7.156-21.531-27.7283.988297.92-12.0510.7711
Percentage of IncreaseDecreaseInAccountsPayableTrade100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInAccruedLiabilities

us-gaap:IncreaseDecreaseInAccruedLiabilities


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value14-18.55727-1.773-2.302-6.36215-25.048-11.9889.61638-22.673-11.10826111.581-19.267385.9190.078-19.04536-14.353-20.967-39.69759-6.416-10.718-84.6328912-2.868-35.73944-5.667-6.45-47.95669-4.008-35.085-56.73921.387-34.61-59.538104-13.536
Percentage of IncreaseDecreaseInAccruedLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInDeferredGasCost

us-gaap:IncreaseDecreaseInDeferredGasCost


Increase
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302011-12-312011-09-302010-12-31
Value0.1120.3670.00.0-1.619-0.6272.246-5.76-2.944.4964.204-0.426-7.3613.1640.866-0.9240.9841.2571.507-0.3121.2450.00.00.00.00.00.0-1.825-7.176-3.407120.00.00.0-2.13.0020.00.0
Percentage of IncreaseDecreaseInDeferredGasCost100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.0100.0100.0100.0100.00.00.00.0100.0100.00.00.0

us-gaap:IncreaseDecreaseInOtherCurrentAssets

us-gaap:IncreaseDecreaseInOtherCurrentAssets


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value-4.1658.1960.251-0.055-52.4463.148-0.01441-1.534-11.6331.19515-7.63412-3.5910.653-0.7331.807-9.57612-11.157-9.4315.25411-10.183-9.8195.6359.006-5.81913-12.76414-9.8392.624-7.0138.4-13.152-4.806-0.232
Percentage of IncreaseDecreaseInOtherCurrentAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInOtherNoncurrentAssets

us-gaap:IncreaseDecreaseInOtherNoncurrentAssets


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value5.2-0.973-10.0665.9887.856-17.928-39.709-4.092
Percentage of IncreaseDecreaseInOtherNoncurrentAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInOtherOperatingLiabilities

us-gaap:IncreaseDecreaseInOtherOperatingLiabilities


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value-0.316-2.3862.3910.1640.607-2.05.8573.9171110-21.333-0.2637.20816-21.775-3.4555.4364.324-4.122-5.331-4.079-6.9772.904-29.0889.0752419-8.864-0.20323-7.205-7.19215-16.9126.495-33.376-18.9851231-8.0287.914-24.3550.6712-10.82322-22.667
Percentage of IncreaseDecreaseInOtherOperatingLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInReceivables

us-gaap:IncreaseDecreaseInReceivables


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value-60.42637636.623-62.293-0.40758-37.963-98.79328101-4.139-88.9334083-12.505-76.272467-1.348-20.455-2.93931-29.463-110.5142760-49.301-126.19510692-26.003-66.26554559.149-73.914-0.14851-29.806-97.4746953-3.586-108.5573367
Percentage of IncreaseDecreaseInReceivables100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInRegulatoryClauseRevenue

us-gaap:IncreaseDecreaseInRegulatoryClauseRevenue


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value-12.57513-4.965-7.9841.55913-0.573-10.529-0.91715-3.394-13.4394.75110.251-13.07-6.39616-16.306-15.904-6.776-2.859-11.702110.0468.8022.2490.948.1415-3.9440.442-5.8532.961-4.6862.2030.4345.33-3.522-10.1420.1861.561-14.195-12.905-13.322-30.132-11.31
Percentage of IncreaseDecreaseInRegulatoryClauseRevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInSecurityDeposits

us-gaap:IncreaseDecreaseInSecurityDeposits


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-231000.01880000.0424000.01973000.0227000.0-511000.0-700000.0-591000.0-1718000.0-5323000.0-1861000.07235000.0-505000.0-3530000.02131000.0
Percentage of IncreaseDecreaseInSecurityDeposits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestExpenseOther

us-gaap:InterestExpenseOther


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value1012000.01698000.01919000.02202000.01420000.01892000.01551000.01081000.01202000.01787000.01073000.0834000.01006000.01233000.0502000.0686000.0846000.0924000.0910000.0-241000.01321000.01237000.01380000.0173000.01007000.01584000.0790000.0623000.01136000.01375000.0949000.0940000.01303000.0526000.01068000.01387000.0828000.01253000.0770000.0540000.01159000.01454000.01401000.01511000.01866000.02002000.01377000.0
Percentage of InterestExpenseOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LeaseCost

us-gaap:LeaseCost


Lease
Period End2020-09-302020-06-302020-03-31
Value2039000.01069000.01076000.0
Percentage of LeaseCost100.0100.0100.0

us-gaap:OperatingLeaseCost

us-gaap:OperatingLeaseCost


Operating
Period End2020-09-302020-06-302020-03-31
Value1257000.0956000.0943000.0
Percentage of OperatingLeaseCost100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value-145.986-24.90334-66.9613.563550.376-13.11924-18.60131-6.904-27.199-9.489-3.1737.9421126-30.9886.499-40.588194427-5.3663514041-4.794-38.4873.08
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Other
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value-14.8570.00.00.0-33.6160.00.00.04.6430.00.00.09.4860.00.00.0-13.0270.00.00.0-19.6160.00.00.0-5.560.00.00.0
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax22.20.00.00.0256.20.0-0.00.0-67.3-0.0-0.0-0.0119.40.00.0-0.0-200.4-0.00.00.0-70.6-0.00.00.0-13.3-0.0-0.00.0

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value-145.986-24.90334-52.1043.563550.376
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax100.0100.0100.077.8100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossBeforeTax

us-gaap:OtherComprehensiveIncomeLossBeforeTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-188.369-30.70748-100.256-31.44351-5.544-26.10930-21.261535.101-33.802-10.061-18.5213.5421.21835-84.842-22.93-128.36-27.8597.5643.734-60.2687.3219692.45-40.199-4.90763100-55.8724-86.0716.9631.429-8.9974929-47.159
Percentage of OtherComprehensiveIncomeLossBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value-201.498-34.37348-71.8414.904760.495
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax us-gaap:DerivativeInstrumentRisk, us-gaap:IncomeStatementLocation

us-gaap:CommodityContract, nfg:OperatingRevenues


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value-202.114-35.12345-72.923.27381-1.555
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax100.3102.294.9101.566.7106.3-314.1

us-gaap:CommodityContract, nfg:PurchasedGas


Other
Period End2020-09-302020-06-302020-03-312019-12-31
Value-0.18-0.427-0.1341.131
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax0.3-8.7-0.2228.5

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax us-gaap:IncomeStatementLocation, us-gaap:InvestmentType

nfg:OperatingRevenues, us-gaap:ForeignExchangeContract


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value0.6160.752.4261.2592.058-4.670.919
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax-0.3-2.25.1-1.842.0-6.1185.7

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value-55.512-9.4713-19.7371.341200.119
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value-13.129-3.666-0.3112436257.352
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax us-gaap:DerivativeInstrumentRisk, us-gaap:IncomeStatementLocation

us-gaap:CommodityContract, nfg:OperatingRevenues


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value-13.281-3.761-0.312636237.541
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax101.2102.699.7106.0101.093.5102.6

us-gaap:CommodityContract, nfg:PurchasedGas


Other
Period End2020-09-302020-06-302020-03-312019-12-31
Value-1.229-0.0221.9090.002
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax-5.0-0.17.60.0

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax us-gaap:IncomeStatementLocation, us-gaap:InvestmentType

nfg:OperatingRevenues, us-gaap:ForeignExchangeContract


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value0.1520.095-0.001-0.237-0.357-0.271-0.191
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax-1.2-2.60.3-1.0-1.0-1.1-2.6

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value-3.617-1.01-0.0866.7659.9076.8172.031
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossTax

us-gaap:OtherComprehensiveIncomeLossTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value-51.895-8.4613-27.293-8.56614-1.549-6.628.7224.335140.455-9.166-3.22-7.7250.3610.43114-35.623-9.551-53.913-11.5892.482.61-25.8273.08492301.033-17.182-2.1032341-23.49110-34.9913.0140.185-3.5642112-19.288-13.933-3.4790.6659.448-7.295
Percentage of OtherComprehensiveIncomeLossTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherNoncashIncomeExpense

us-gaap:OtherNoncashIncomeExpense


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value-1.053-3.855-2.887-0.8824.155-7.889-1.911-0.6440.033-5.815-2.182-3.822-4.259-4.374-3.678-5.392-3.371-4.106-3.607-2.935-3.579-2.688-3.418-2.494-2.62-2.351-2.358-3.094-11.087-1.9772.09534-5.135-6.686-7.92319-2.349-1.894-2.37523-1.648-2.16-3.543
Percentage of OtherNoncashIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsForProceedsFromOtherInvestingActivities

us-gaap:PaymentsForProceedsFromOtherInvestingActivities


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value0.872-0.246-11.8495.3310.0411.045-5.2127.1660.4550.0672.549-1.377.114-2.743-2.612-11.4026.961-1.0724.297-1.927-7.0862.493155.546-0.1970.0331.229-1.2860.231-1.312-3.615-1.3630.44-0.0883.533-1.7130.478-0.1770.9660.0-0.1892.7990.298-0.0220.158-0.1320.247
Percentage of PaymentsForProceedsFromOtherInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsForRepurchaseOfEquity

us-gaap:PaymentsForRepurchaseOfEquity


Payments
Period End2021-06-302021-03-312020-12-312020-03-312019-12-312019-03-312018-12-312017-12-31
Value71000.08000.03526000.06000.04147000.0631000.08233000.01501000.0
Percentage of PaymentsForRepurchaseOfEquity100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromIssuanceOrSaleOfEquity

us-gaap:ProceedsFromIssuanceOrSaleOfEquity


Proceeds
Period End2020-09-302018-09-302017-09-302011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value-0.101-0.1521.5613.879-1.6380.271-3.104-0.741166.7273.997
Percentage of ProceedsFromIssuanceOrSaleOfEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProvisionForDoubtfulAccounts

us-gaap:ProvisionForDoubtfulAccounts


Provision
Period End2021-06-302021-03-312020-12-31
Value130.0063950.004679
Percentage of ProvisionForDoubtfulAccounts100.0100.0100.0

us-gaap:PublicUtilitiesRequestedRateIncreaseDecreaseAmount us-gaap:StatementGeographical

us-gaap:PublicUtilitiesRequestedRateIncreaseDecreaseAmount

stpr:PA


Public
Period End2021-06-30
Value-7700000.0
Percentage of PublicUtilitiesRequestedRateIncreaseDecreaseAmount100.0

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax


Reclassification
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value-9.512-2.656-0.2256.00226185.3216.372.756-3.411-7.286-11.55-2.563-2.6487.6234.761106.0581819333539262931142.251-6.211-15.475.884
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Reclassification
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value-11.7950.00.00.0-5.6340.00.00.0-7.2670.00.00.0-8.5040.00.00.0-6.3450.00.00.0-5.8420.00.00.0-5.8330.00.00.0
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax-196.50.00.00.0-88.40.0-0.0-0.062.9-0.0-0.00.0-178.60.00.00.0-31.90.00.00.0-21.90.00.00.0-259.1-0.0-0.00.0

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Reclassification
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value-9.512-2.656-0.2251726185.321
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax100.0100.0100.0296.5100.0100.0100.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue us-gaap:AwardType

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue

nfg:NonPerformanceBasedRestrictedStockUnits


Share
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-312019-06-302019-03-312018-12-312018-06-302018-03-312017-12-312017-06-302017-03-312016-12-312016-06-302016-03-312015-12-312015-06-302015-03-312014-12-312014-06-302014-03-312013-12-312013-06-302013-03-312012-12-31
Value0-0.0238.00040.38-0.02049.720051.2300.0152.120035.570064.040.01065.232.93047.2
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue0.0100.0100.00.00.0100.0100.00.0100.00.00.0100.00.0100.0100.00.00.0100.00.00.0100.0100.00.0100.0100.00.0100.0

us-gaap:PerformanceShares


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-03-312012-12-31
Value0039.1900043.3200055.6700050.9500056.3900030.7100065.2600067.161.0248.49
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue0.0-0.0103.10.00.00.0107.30.0-0.00.0112.00.00.00.099.50.00.00.0108.20.00.00.086.30.00.00.0101.90.00.00.0103.00.0102.7

us-gaap:ShortTermLeaseCost

us-gaap:ShortTermLeaseCost


Short
Period End2020-09-302020-06-302020-03-312019-12-31
Value0.7320.0460.0760.064
Percentage of ShortTermLeaseCost100.0100.0100.0100.0

us-gaap:ShortTermLeaseCost us-gaap:PropertyPlantAndEquipmentByType

us-gaap:OilAndGasProperties


Short
Period End2020-09-302020-06-302020-03-312019-12-31
Value1.7693.1746.7767.512
Percentage of ShortTermLeaseCost241.76900.08915.811737.5

us-gaap:StockIssuedDuringPeriodSharesNewIssues us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodSharesNewIssues

us-gaap:CommonStock


Stock
Period End2020-09-302020-06-30
Value04370000.0
Percentage of StockIssuedDuringPeriodSharesNewIssues0.0100.0

us-gaap:StockIssuedDuringPeriodSharesOther us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodSharesOther

us-gaap:CommonStock


Stock
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
Value9000.011000.0198000.011000.012000.010000.0237000.08000.06000.030000.0314000.013000.062000.0121000.0218000.0
Percentage of StockIssuedDuringPeriodSharesOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodValueOther us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodValueOther

us-gaap:AdditionalPaidInCapital


Stock
Period End2021-06-302021-03-312020-06-302020-03-312019-06-302018-12-312018-09-302018-06-302018-03-312017-12-31
Value0.4320.4230.4260.4220.352-8.0640.2252.7116.2150.191
Percentage of StockIssuedDuringPeriodValueOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CommonStock


Stock
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
Value0.0090.0110.1980.0110.0120.010.2370.0080.0060.030.3140.0130.0620.1210.218
Percentage of StockIssuedDuringPeriodValueOther2.12.60.00.02.82.40.00.01.70.0-3.95.82.31.9114.1

us-gaap:StockRepurchasedDuringPeriodValue us-gaap:StatementEquityComponents

us-gaap:StockRepurchasedDuringPeriodValue

us-gaap:AdditionalPaidInCapital


Stock
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value432000.0423000.0-3285000.0413000.0426000.0422000.0-3946000.0416000.0353000.0-277000.0-8064000.0
Percentage of StockRepurchasedDuringPeriodValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:SubleaseIncome

us-gaap:SubleaseIncome


Sublease
Period End2020-09-302020-06-302020-03-31
Value95000.041000.080000.0
Percentage of SubleaseIncome100.0100.0100.0

us-gaap:TaxesExcludingIncomeAndExciseTaxes

us-gaap:TaxesExcludingIncomeAndExciseTaxes


Taxes
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-31
Value2423222121222320212224202022202021222019202120212224202122252018212219202030191820231918182018
Percentage of TaxesExcludingIncomeAndExciseTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:UtilitiesOperatingExpenseMaintenanceAndOperations us-gaap:StatementBusinessSegments

us-gaap:UtilitiesOperatingExpenseMaintenanceAndOperations

nfg:ExplorationandProductionandOtherCategory


Utilities
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
Value4341423932393638354032353139354234373036354245434650
Percentage of UtilitiesOperatingExpenseMaintenanceAndOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:PipelineandStorageandGathering


Utilities
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
Value3128283124272530282724322422202923232224232119232019
Percentage of UtilitiesOperatingExpenseMaintenanceAndOperations72.567.266.978.375.068.370.579.680.467.976.093.479.557.256.468.068.261.574.467.565.550.142.954.143.938.5

nfg:UtilityandEnergyMarketing


Utilities
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
Value4252444243514339394843424561514044635041465747464462
Percentage of UtilitiesOperatingExpenseMaintenanceAndOperations98.8124.3106.8105.8135.6129.4117.9101.4111.0121.0133.9120.7146.5155.1144.594.3130.4170.0165.5113.3131.6133.4104.3107.195.9123.3

us-gaap:VariableLeaseCost

us-gaap:VariableLeaseCost


Variable
Period End2020-09-302020-06-302020-03-31
Value145000.0108000.0137000.0
Percentage of VariableLeaseCost100.0100.0100.0

dei:EntityCommonStockSharesOutstanding

dei:EntityCommonStockSharesOutstanding


Entity
Period End2021-07-312021-04-302021-01-312020-10-31
Value91919190
Percentage of EntityCommonStockSharesOutstanding100.0100.0100.0100.0

nfg:AcceleratedAMTCreditRefundReceivedUnderCARESAct

nfg:AcceleratedAMTCreditRefundReceivedUnderCARESAct


Accelerated
Period End2020-09-30
Value42
Percentage of AcceleratedAMTCreditRefundReceivedUnderCARESAct100.0

nfg:AnticipatedProceedsFromSaleOfCertainTimberAndOtherAssets

nfg:AnticipatedProceedsFromSaleOfCertainTimberAndOtherAssets


Anticipated
Period End2020-08-05
Value115
Percentage of AnticipatedProceedsFromSaleOfCertainTimberAndOtherAssets100.0

nfg:AssetAcquisitionAssets

nfg:AssetAcquisitionAssets


Asset
Period End2020-09-30
Value506
Percentage of AssetAcquisitionAssets100.0

nfg:AssetAcquisitionAssets us-gaap:StatementBusinessSegments

nfg:ExplorationAndProduction


Asset
Period End2020-09-30
Value282
Percentage of AssetAcquisitionAssets55.9

nfg:Gathering


Asset
Period End2020-09-30
Value223
Percentage of AssetAcquisitionAssets44.1

nfg:AssetAcquisitionConsiderationTransferred

nfg:AssetAcquisitionConsiderationTransferred


Asset
Period End2020-09-30
Value506
Percentage of AssetAcquisitionConsiderationTransferred100.0

nfg:AssetAcquisitionInventory

nfg:AssetAcquisitionInventory


Asset
Period End2020-09-30
Value1241000.0
Percentage of AssetAcquisitionInventory100.0

nfg:AssetAcquisitionInventory us-gaap:StatementBusinessSegments

nfg:ExplorationAndProduction


Asset
Period End2020-09-30
Value1132000.0
Percentage of AssetAcquisitionInventory91.2

nfg:Gathering


Asset
Period End2020-09-30
Value109000.0
Percentage of AssetAcquisitionInventory8.8

nfg:AssetAcquisitionTransactionCosts

nfg:AssetAcquisitionTransactionCosts


Asset
Period End2020-09-30
Value2350000.0
Percentage of AssetAcquisitionTransactionCosts100.0

nfg:CommittedCreditFacilityDebtToCapitalizationRatioCeilingTestImpairmentAdjustmentAmount

nfg:CommittedCreditFacilityDebtToCapitalizationRatioCeilingTestImpairmentAdjustmentAmount


Committed
Period End2020-09-30
Value163
Percentage of CommittedCreditFacilityDebtToCapitalizationRatioCeilingTestImpairmentAdjustmentAmount100.0

nfg:CommittedCreditFacilityDebttoCapitalizationRatioCeilingTestImpairmentAdjustment

nfg:CommittedCreditFacilityDebttoCapitalizationRatioCeilingTestImpairmentAdjustment


Committed
Period End2020-09-30
Value50.0
Percentage of CommittedCreditFacilityDebttoCapitalizationRatioCeilingTestImpairmentAdjustment100.0

nfg:CommittedCreditFacilityDebttoCapitalizationRatioCeilingTestImpairmentMaximumAdjustment

nfg:CommittedCreditFacilityDebttoCapitalizationRatioCeilingTestImpairmentMaximumAdjustment


Committed
Period End2020-09-30
Value250
Percentage of CommittedCreditFacilityDebttoCapitalizationRatioCeilingTestImpairmentMaximumAdjustment100.0

nfg:CostOfRemovalRegulatoryLiability

nfg:CostOfRemovalRegulatoryLiability


Cost
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
Value241237234230227224222221218215214212213207205204199196195193191189184184180178175173166165163157151149147139148146144135133131125124
Percentage of CostOfRemovalRegulatoryLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:CreditRiskExposurePerCounterparty nfg:CreditRiskExposure, us-gaap:DerivativeInstrumentRisk

nfg:CreditRiskExposurePerCounterparty

nfg:LessThan100000, nfg:OvertheCounterSwapsNoCostCollarsandForeignCurrencyForwardContracts


Credit
Period End2021-06-30
Value100000.0
Percentage of CreditRiskExposurePerCounterparty100.0

nfg:CreditRiskExposurePerCounterparty us-gaap:DerivativeInstrumentRisk

nfg:OverTheCounterSwapsNoCostCollarsAndForeignCurrencyForwardContracts


Credit
Period End2020-09-30
Value1200000.0
Percentage of CreditRiskExposurePerCounterparty0.0

nfg:OvertheCounterSwapsNoCostCollarsandForeignCurrencyForwardContracts


Credit
Period End2021-03-312020-12-31
Value800000.01800000.0
Percentage of CreditRiskExposurePerCounterparty0.00.0

nfg:CustomerAdvances

nfg:CustomerAdvances


Customer
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value16150.5610.61513130.1660.4337.35113
Percentage of CustomerAdvances100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:DeferredTaxAssetsPensionAndOtherPostRetirementCosts

nfg:DeferredTaxAssetsPensionAndOtherPostRetirementCosts


Deferred
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-09-30
Value958762123195168124137132130130276275274276264263262263227223
Percentage of DeferredTaxAssetsPensionAndOtherPostRetirementCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:DeferredTaxLiabilitiesPensionAndOtherPostRetirementCosts

nfg:DeferredTaxLiabilitiesPensionAndOtherPostRetirementCosts


Deferred
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-09-30
Value54553979151141113122121123124244239240236205208213217183177
Percentage of DeferredTaxLiabilitiesPensionAndOtherPostRetirementCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityBeforeTax us-gaap:RetirementPlanTaxStatus

nfg:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityBeforeTax

us-gaap:NonqualifiedPlan


Defined
Period End2020-09-302019-09-302018-09-302017-09-30
Value34332224
Percentage of DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityBeforeTax100.0100.0100.0100.0

nfg:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityBeforeTax us-gaap:RetirementPlanType

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-30
Value2524-4.45115
Percentage of DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityBeforeTax75.373.4-19.565.3

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-30
Value218220140210
Percentage of DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityBeforeTax642.8658.7616.7863.1

nfg:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityNetGainsLossesBeforeTax us-gaap:RetirementPlanTaxStatus

nfg:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityNetGainsLossesBeforeTax

us-gaap:NonqualifiedPlan


Defined
Period End2020-09-302019-09-302018-09-302017-09-30
Value34332224
Percentage of DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityNetGainsLossesBeforeTax100.0100.0100.0100.0

nfg:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityNetGainsLossesBeforeTax us-gaap:RetirementPlanType

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-30
Value2827-1.19319
Percentage of DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityNetGainsLossesBeforeTax82.381.8-5.280.5

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-30
Value215216135203
Percentage of DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityNetGainsLossesBeforeTax632.1645.7593.9837.9

nfg:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityNetPriorServiceCostCreditBeforeTax us-gaap:RetirementPlanType

nfg:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityNetPriorServiceCostCreditBeforeTax

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-30
Value2.4012.8293.2583.687
Percentage of DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityNetPriorServiceCostCreditBeforeTax100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-30
Value-3.641-4.37-5.195-6.133
Percentage of DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeRegulatoryAssetRegulatoryLiabilityNetPriorServiceCostCreditBeforeTax-151.6-154.5-159.5-166.3

nfg:DepreciablePlantAssets

nfg:DepreciablePlantAssets


Depreciable
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-302010-09-30
Value11906107881007695709167857577917006617151455322
Percentage of DepreciablePlantAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:DepreciablePlantAssets us-gaap:StatementBusinessSegments

nfg:AllOtherAndCorporate


Depreciable
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-30
Value20112108109109109108109110
Percentage of DepreciablePlantAssets0.21.01.11.11.21.31.41.61.8

nfg:ExplorationAndProduction


Depreciable
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-30
Value6384574752224925464545563996343728282042
Percentage of DepreciablePlantAssets53.653.351.851.550.753.151.349.145.839.7

nfg:Gathering


Depreciable
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-30
Value84957752748445430723913086
Percentage of DepreciablePlantAssets7.15.35.25.15.03.63.11.91.4

nfg:PipelineAndStorage


Depreciable
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-30
Value2418219121102002195617101609154714061260
Percentage of DepreciablePlantAssets20.320.320.920.921.320.020.722.122.824.5

nfg:Utility


Depreciable
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-30
Value2234215921042045199818881833177817371695
Percentage of DepreciablePlantAssets18.820.020.921.421.822.023.525.428.233.0

nfg:EarningsReinvestedInBusinessAvailableForDividends

nfg:EarningsReinvestedInBusinessAvailableForDividends


Earnings
Period End2020-09-30
Value848
Percentage of EarningsReinvestedInBusinessAvailableForDividends100.0

nfg:EmissionAllowances

nfg:EmissionAllowances


Emission
Period End2021-06-302021-03-312020-12-312020-09-302019-09-30
Value1818181810
Percentage of EmissionAllowances100.0100.0100.0100.0100.0

nfg:FairValueAssetsLiabilitiesMeasuredOnRecurringBasisNet

nfg:FairValueAssetsLiabilitiesMeasuredOnRecurringBasisNet


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-09-30
Value6.31315320590710289164164211181211271358290235650407356229298281384352411573394359140130175105139221899079219266289143184356
Percentage of FairValueAssetsLiabilitiesMeasuredOnRecurringBasisNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:FairValueAssetsLiabilitiesMeasuredOnRecurringBasisNet us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueInputsLevel1


Fair
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
Value211170192124648196124116175176178309384283220616345294198186156133761423329466681321746092159126687714820522873
Percentage of FairValueAssetsLiabilitiesMeasuredOnRecurringBasisNet3355.1111.193.4138.691.367.875.870.782.897.184.2114.3107.497.493.594.784.882.686.862.455.634.621.734.558.023.818.649.0101.499.457.666.072.1140.775.098.167.777.178.851.3

us-gaap:FairValueInputsLevel2


Fair
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-205.495-17.12713-34.7562933948365.32833-38.666-26.6367.4211534616130111124251275267238295287701.072.462465269-19.96836218712911675
Percentage of FairValueAssetsLiabilitiesMeasuredOnRecurringBasisNet-3255.1-11.16.6-38.68.732.224.229.317.22.915.8-14.3-7.42.66.55.315.217.413.237.644.465.478.365.041.675.079.950.00.81.444.237.731.4-22.240.526.739.948.840.152.5

nfg:FairValueAssetsMeasuredOnRecurringBasisTotal

nfg:FairValueAssetsMeasuredOnRecurringBasisTotal


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-09-30
Value211174210134713297171169216187213320396302242651408357236299282394360421582407370141158198112140223131104103235332337152229376
Percentage of FairValueAssetsMeasuredOnRecurringBasisTotal100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:FairValueAssetsMeasuredOnRecurringBasisTotal us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueInputsLevel1


Fair
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
Value2111701921246522031321231801771803123862842226173462952031881591438715734411083711331756193161128708015321123176
Percentage of FairValueAssetsMeasuredOnRecurringBasisTotal100.097.791.493.191.468.477.572.683.794.884.597.597.694.291.994.784.982.686.062.956.336.424.437.359.127.122.650.683.788.754.866.972.297.967.277.665.463.668.650.2

us-gaap:FairValueInputsLevel2


Fair
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
Value7.18620383683103465245234326283332406873621191372552842722402972887556487657722459419512110675
Percentage of FairValueAssetsMeasuredOnRecurringBasisTotal3.411.618.327.411.734.727.430.720.812.520.38.37.211.013.26.216.720.626.239.948.764.978.964.641.373.077.953.735.624.468.240.732.319.056.640.240.436.431.449.2

nfg:FairValueAssetsMeasuredOnRecurringBasisTotal us-gaap:FairValueConcentrationOfRiskDisclosureItems

us-gaap:FairValueConcentrationOfCreditRiskMasterNettingArrangements


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-09-30
Value-7.18-16.138-20.504-27.458-22.37-9.206-8.331-5.59-9.717-13.732-10.107-18.559-18.744-15.961-12.352-5.576-6.544-11.293-28.906-8.473-14.169-10.136
Percentage of FairValueAssetsMeasuredOnRecurringBasisTotal-3.4-9.2-9.7-20.5-3.1-3.1-4.9-3.3-4.5-7.3-4.7-5.8-4.7-5.3-5.1-0.9-1.6-3.2-12.2-2.8-5.0-2.4

nfg:FairValueLiabilitiesMeasuredOnRecurringBasisTotal

nfg:FairValueLiabilitiesMeasuredOnRecurringBasisTotal


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-09-30
Value205214.513433.2277.6526.2825.5744.5635.7492.1124938116.5791.1030.9221.4717.3121.4621.7049.8647.969109.12813110.75928227.1610.6392.2174113241666489.6744420
Percentage of FairValueLiabilitiesMeasuredOnRecurringBasisTotal100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:FairValueLiabilitiesMeasuredOnRecurringBasisTotal us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueInputsLevel2


Fair
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
Value212372571219.9956.8724.0158.594189.928655425165.7166.34111317.659124.4588.2994.9362.1261.811.3475.5235545304.4522.6264422207.692-8.557-10.0790.0
Percentage of FairValueLiabilitiesMeasuredOnRecurringBasisTotal103.5176.0554.3162.4671.6130.6109.472.0188.3314.2470.1132.9144.6226.2254.5518.2687.7795.1434.5523.9758.045.2104.149.023.313.712.2727.7193.8206.1421.3696.7118.4108.1162.183.947.5-12.8-20.90.0

nfg:FairValueLiabilitiesMeasuredOnRecurringBasisTotal us-gaap:FairValueConcentrationOfRiskDisclosureItems

us-gaap:FairValueConcentrationOfCreditRiskMasterNettingArrangements


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-09-30
Value-7.18-16.138-20.504-27.458-22.37-9.206-8.331-5.59-9.717-13.732-10.107-18.559-18.744-15.961-12.352-5.576-6.544-11.293-28.906-8.473-14.169-10.136
Percentage of FairValueLiabilitiesMeasuredOnRecurringBasisTotal-3.5-76.0-454.3-62.4-693.2-120.3-132.6-100.3-213.0-238.9-478.6-37.8-49.3-139.1-187.7-505.5-709.8-767.7-395.3-579.5-831.5-100.6

nfg:FirstInstallmentOfAMTCreditRefunds

nfg:FirstInstallmentOfAMTCreditRefunds


First
Period End2020-09-30
Value42
Percentage of FirstInstallmentOfAMTCreditRefunds100.0

nfg:FullCostCeilingExceedsBookValueOfOilAndGasProperties

nfg:FullCostCeilingExceedsBookValueOfOilAndGasProperties


Full
Period End2021-06-302021-03-31
Value409145
Percentage of FullCostCeilingExceedsBookValueOfOilAndGasProperties100.0100.0

nfg:InterestPayableOnLongTermDebt

nfg:InterestPayableOnLongTermDebt


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value4517452731182918291830192826273528342834283430361829182918291829183016291629162515251530
Percentage of InterestPayableOnLongTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:LiabilityforRoyaltyandWorkingInterestCurrent

nfg:LiabilityforRoyaltyandWorkingInterestCurrent


Liabilityfor
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
Value232222151213201819212612
Percentage of LiabilityforRoyaltyandWorkingInterestCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:MaterialsAndSuppliesAtAverageCost

nfg:MaterialsAndSuppliesAtAverageCost


Materials
Period End2021-06-302021-03-312020-12-312020-09-302019-09-30
Value3533333329
Percentage of MaterialsAndSuppliesAtAverageCost100.0100.0100.0100.0100.0

nfg:MaximumCreditRiskExposurePerCounterparty us-gaap:DerivativeInstrumentRisk

nfg:MaximumCreditRiskExposurePerCounterparty

nfg:OverTheCounterSwapsNoCostCollarsAndForeignCurrencyForwardContracts


Maximum
Period End2020-09-30
Value3900000.0
Percentage of MaximumCreditRiskExposurePerCounterparty100.0

nfg:OvertheCounterSwapsNoCostCollarsandForeignCurrencyForwardContracts


Maximum
Period End2021-03-312020-12-31
Value1600000.04200000.0
Percentage of MaximumCreditRiskExposurePerCounterparty0.00.0

nfg:MediumTermNotesPayable us-gaap:LongtermDebtType

nfg:MediumTermNotesPayable

nfg:SevenPointFourPercentDueMarchTwoThousandTwentyThreeToJuneTwoThousandTwentyFive


Medium
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-30
Value999999999999999999249
Percentage of MediumTermNotesPayable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:NetAcresAcquiredInTiogaCounty us-gaap:SubsequentEventType

nfg:NetAcresAcquiredInTiogaCounty

us-gaap:SubsequentEvent


Net
Period End2020-07-31
Value200000.0
Percentage of NetAcresAcquiredInTiogaCounty100.0

nfg:NetHedgingGainsLossesInAccumulatedOtherComprehensiveIncomeLoss

nfg:NetHedgingGainsLossesInAccumulatedOtherComprehensiveIncomeLoss


Net
Period End2020-09-30
Value34
Percentage of NetHedgingGainsLossesInAccumulatedOtherComprehensiveIncomeLoss100.0

nfg:NetHedgingGainsLossesinAccumulatedOtherComprehensiveIncomeLoss

nfg:NetHedgingGainsLossesinAccumulatedOtherComprehensiveIncomeLoss


Net
Period End2021-06-302021-03-312020-12-31
Value-205.5-17.113
Percentage of NetHedgingGainsLossesinAccumulatedOtherComprehensiveIncomeLoss100.0100.0100.0

nfg:NoncurrentAssets1 us-gaap:StatementGeographical

nfg:NoncurrentAssets1

country:US


Noncurrent
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-30
Value6597609954915285522361896362576955794809
Percentage of NoncurrentAssets1100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:NonmonetaryNotionalAmountOfPriceRiskCashFlowHedgeDerivativesCrudeOil us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship

nfg:NonmonetaryNotionalAmountOfPriceRiskCashFlowHedgeDerivativesCrudeOil

nfg:CrudeOilBbls, nfg:CashFlowHedges


Nonmonetary
Period End2020-09-30
Value1548000.0
Percentage of NonmonetaryNotionalAmountOfPriceRiskCashFlowHedgeDerivativesCrudeOil100.0

nfg:CrudeOilBbls, us-gaap:CashFlowHedging


Nonmonetary
Period End2021-06-302021-03-312020-12-31
Value2409000.02082000.01605000.0
Percentage of NonmonetaryNotionalAmountOfPriceRiskCashFlowHedgeDerivativesCrudeOil0.00.00.0

nfg:NonmonetaryNotionalAmountOfPriceRiskCashFlowHedgeDerivativesNaturalGas us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship

nfg:NonmonetaryNotionalAmountOfPriceRiskCashFlowHedgeDerivativesNaturalGas

nfg:NaturalGasMmcf, nfg:CashFlowHedges


Nonmonetary
Period End2020-09-30
Value0.2867
Percentage of NonmonetaryNotionalAmountOfPriceRiskCashFlowHedgeDerivativesNaturalGas100.0

nfg:NaturalGasMmcf, us-gaap:CashFlowHedging


Nonmonetary
Period End2021-06-302021-03-312020-12-31
Value0.35940.25330.282
Percentage of NonmonetaryNotionalAmountOfPriceRiskCashFlowHedgeDerivativesNaturalGas0.00.00.0

nfg:Notes us-gaap:LongtermDebtType

nfg:Notes

nfg:A375To550DueDecember2021ToSeptember2028Domain


Notesus-gaap:
Period End2020-09-302019-09-30
Value25502050
Percentage of Notes100.0100.0

nfg:ProvedUndevelopedReservesAdditions

nfg:ProvedUndevelopedReservesAdditions


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-30
Value7000575000431000269000102000496000290000221000289000212000
Percentage of ProvedUndevelopedReservesAdditions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:ProvedUndevelopedReservesConversionsToDevelopedReserves

nfg:ProvedUndevelopedReservesConversionsToDevelopedReserves


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-302010-09-30
Value363000297000284000159000110000168000229000160000970008300017000
Percentage of ProvedUndevelopedReservesConversionsToDevelopedReserves100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:ProvedUndevelopedReservesConversionsToDevelopedReserves us-gaap:StatementGeographical

nfg:MarcellusShaleFields


Proved
Period End2020-09-302019-09-302018-09-302017-09-30
Value146000186000264000158000
Percentage of ProvedUndevelopedReservesConversionsToDevelopedReserves40.262.693.099.4

nfg:UticaShale


Proved
Period End2020-09-302019-09-302018-09-30
Value21400010600018000
Percentage of ProvedUndevelopedReservesConversionsToDevelopedReserves59.035.76.3

nfg:WestCoastRegion


Proved
Period End2020-09-302019-09-302018-09-302017-09-30
Value3000500020001000
Percentage of ProvedUndevelopedReservesConversionsToDevelopedReserves0.81.70.70.6

nfg:ProvedUndevelopedReservesDecrease

nfg:ProvedUndevelopedReservesDecrease


Proved
Period End2020-09-30
Value467000
Percentage of ProvedUndevelopedReservesDecrease100.0

nfg:ProvedUndevelopedReservesPercentage

nfg:ProvedUndevelopedReservesPercentage


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-302010-09-302009-09-30
Value36.00.390.460.270.110.330.510.510.390.470.190.19
Percentage of ProvedUndevelopedReservesPercentage100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:ProvedUndevelopedReservesRemoved

nfg:ProvedUndevelopedReservesRemoved


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-30
Value17900055000500054000960003900033000
Percentage of ProvedUndevelopedReservesRemoved100.0100.0100.0100.0100.0100.0100.0

nfg:ProvedUndevelopedReservesRemoved us-gaap:StatementGeographical

nfg:MarcellusShaleFields


Proved
Period End2020-09-302019-09-302016-09-302015-09-302014-09-30
Value1400013000740003700024000
Percentage of ProvedUndevelopedReservesRemoved7.823.677.194.972.7

nfg:UticaShale


Proved
Period End2020-09-302019-09-30
Value16500042000
Percentage of ProvedUndevelopedReservesRemoved92.276.4

nfg:ProvedUndevelopedReservesRevisions

nfg:ProvedUndevelopedReservesRevisions


Proved
Period End2020-09-302015-09-302014-09-302013-09-302012-09-302011-09-302010-09-30
Value48000-26000.0-12000.0190007700020004000
Percentage of ProvedUndevelopedReservesRevisions100.0100.0100.0100.0100.0100.0100.0

nfg:ProvedUndevelopedReservesUpwardRevisions

nfg:ProvedUndevelopedReservesUpwardRevisions


Proved
Period End2020-09-302019-09-302018-09-302017-09-30
Value20000380006000013000
Percentage of ProvedUndevelopedReservesUpwardRevisions100.0100.0100.0100.0

nfg:PurchasePriceToAcquireUpstreamAssetsAndMidstreamGatheringAssets

nfg:PurchasePriceToAcquireUpstreamAssetsAndMidstreamGatheringAssets


Purchase
Period End2020-09-30
Value503
Percentage of PurchasePriceToAcquireUpstreamAssetsAndMidstreamGatheringAssets100.0

nfg:RecoverableFutureTaxes

nfg:RecoverableFutureTaxes


Recoverable
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
Value118117117118116115116115113113114115115115116181182179179177172172172168168163164163162161162163152150152150147146145144151152150149
Percentage of RecoverableFutureTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:RecoverableFutureTaxes us-gaap:ValuationAllowanceByDeferredTaxAsset

nfg:DeferredIncomeTaxes


Recoverable
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-09-30
Value118115115181177168163162161162163152150152150147146145144151149
Percentage of RecoverableFutureTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisableWeightedAverageExercisePrice us-gaap:AwardType

nfg:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisableWeightedAverageExercisePrice

us-gaap:StockAppreciationRightsSARS


Share
Period End2020-09-30
Value56.07
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisableWeightedAverageExercisePrice100.0

nfg:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpirationsInPeriodWeightedAverageExercisePrice us-gaap:AwardType

nfg:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpirationsInPeriodWeightedAverageExercisePrice

us-gaap:StockAppreciationRightsSARS


Share
Period End2020-09-30
Value52.18
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpirationsInPeriodWeightedAverageExercisePrice100.0

nfg:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageExercisePrice us-gaap:AwardType

nfg:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageExercisePrice

us-gaap:StockAppreciationRightsSARS


Share
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-30
Value56.0754.950.748.6448.1948.748.11
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageExercisePrice100.0100.0100.0100.0100.0100.0100.0

nfg:TaxesRefundableToCustomers

nfg:TaxesRefundableToCustomers


Taxes
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
Value3533553573573573603613663663653663703663653669593939393919394899590909190908485656566666565656570696969
Percentage of TaxesRefundableToCustomers100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:TaxesRefundableToCustomers us-gaap:ValuationAllowanceByDeferredTaxAsset

nfg:DeferredIncomeTaxes


Taxes
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-09-30
Value357366370959389919090848565656666656565657069
Percentage of TaxesRefundableToCustomers100.0100.0100.0100.0100.099.9100.0100.0100.0100.0100.1100.0100.1100.0100.0100.1100.199.999.999.9100.0

nfg:TotalOtherAssets

nfg:TotalOtherAssets


Total
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-09-30
Value583582594599665656590
Percentage of TotalOtherAssets100.0100.0100.0100.0100.0100.0100.0

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesCashInflows

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesCashInflows


Future
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value64938738782261443768
Percentage of FutureNetCashFlowsRelatingToProvedOilAndGasReservesCashInflows100.0100.0100.0100.0100.0

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesDevelopmentCosts

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesDevelopmentCosts


Future
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value501797559411375
Percentage of FutureNetCashFlowsRelatingToProvedOilAndGasReservesDevelopmentCosts100.0100.0100.0100.0100.0

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesIncomeTaxExpense

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesIncomeTaxExpense


Future
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value454115911251160303
Percentage of FutureNetCashFlowsRelatingToProvedOilAndGasReservesIncomeTaxExpense100.0100.0100.0100.0100.0

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesNetCashFlows

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesNetCashFlows


Future
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value23873791353021941094
Percentage of FutureNetCashFlowsRelatingToProvedOilAndGasReservesNetCashFlows100.0100.0100.0100.0100.0

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesProductionCosts

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesProductionCosts


Future
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value31492989260623781994
Percentage of FutureNetCashFlowsRelatingToProvedOilAndGasReservesProductionCosts100.0100.0100.0100.0100.0

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesTenPercentAnnualDiscountForEstimatedTimingOfCashFlows

srt:FutureNetCashFlowsRelatingToProvedOilAndGasReservesTenPercentAnnualDiscountForEstimatedTimingOfCashFlows


Future
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value1164205418101080452
Percentage of FutureNetCashFlowsRelatingToProvedOilAndGasReservesTenPercentAnnualDiscountForEstimatedTimingOfCashFlows100.0100.0100.0100.0100.0

srt:ProvedDevelopedAndUndevelopedReservesNet us-gaap:Energy

srt:ProvedDevelopedAndUndevelopedReservesNet

srt:CrudeOilAndNGLPerBarrel


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value22100.024873.027663.030207.029009.0
Percentage of ProvedDevelopedAndUndevelopedReservesNet100.0100.0100.0100.0100.0

srt:NaturalGasPerThousandCubicFeet


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value3325100.02949500.02357300.01973100.01674600.0
Percentage of ProvedDevelopedAndUndevelopedReservesNet15045.611858.38521.66532.05772.6

srt:ProvedDevelopedAndUndevelopedReservesNet us-gaap:Energy, us-gaap:StatementGeographical

srt:CrudeOilAndNGLPerBarrel, nfg:AppalachianRegion


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value12.013.014.028.073.0
Percentage of ProvedDevelopedAndUndevelopedReservesNet0.10.10.10.10.3

srt:CrudeOilAndNGLPerBarrel, nfg:WestCoastRegion


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value22088.024860.027649.030179.028936.0
Percentage of ProvedDevelopedAndUndevelopedReservesNet99.999.999.999.999.7

srt:NaturalGasPerThousandCubicFeet, nfg:AppalachianRegion


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value3296100.02915900.02320500.01926600.01631500.0
Percentage of ProvedDevelopedAndUndevelopedReservesNet14914.511723.18388.56378.05623.9

srt:NaturalGasPerThousandCubicFeet, nfg:WestCoastRegion


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value28972.033633.036840.046506.043124.0
Percentage of ProvedDevelopedAndUndevelopedReservesNet131.1135.2133.2154.0148.7

srt:ProvedDevelopedReservesVolume us-gaap:Energy

srt:ProvedDevelopedReservesVolume

srt:CrudeOilAndNGLPerBarrel


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value22100.024259.026703.029799.028771.0
Percentage of ProvedDevelopedReservesVolume100.0100.0100.0100.0100.0

srt:NaturalGasPerThousandCubicFeet


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value2773800.01934800.01606500.01363100.01132600.0
Percentage of ProvedDevelopedReservesVolume12551.27975.66016.34574.33936.7

srt:ProvedDevelopedReservesVolume us-gaap:Energy, us-gaap:StatementGeographical

srt:CrudeOilAndNGLPerBarrel, nfg:AppalachianRegion


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value12.013.014.028.073.0
Percentage of ProvedDevelopedReservesVolume0.10.10.10.10.3

srt:CrudeOilAndNGLPerBarrel, nfg:WestCoastRegion


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value22088.024246.026689.029771.028698.0
Percentage of ProvedDevelopedReservesVolume99.999.999.999.999.7

srt:NaturalGasPerThousandCubicFeet, nfg:AppalachianRegion


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value2744900.01901200.01569700.01316600.01089500.0
Percentage of ProvedDevelopedReservesVolume12420.17836.95878.34418.33786.8

srt:NaturalGasPerThousandCubicFeet, nfg:WestCoastRegion


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value28972.033633.036840.046506.043124.0
Percentage of ProvedDevelopedReservesVolume131.1138.6138.0156.1149.9

srt:ProvedUndevelopedReserveVolume

srt:ProvedUndevelopedReserveVolume


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value5510001018000757000612000543000
Percentage of ProvedUndevelopedReserveVolume100.0100.0100.0100.0100.0

srt:ProvedUndevelopedReserveVolume us-gaap:Energy

srt:NaturalGasPerThousandCubicFeet


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value0.5512621.0147240.750810.6100180.541959
Percentage of ProvedUndevelopedReserveVolume0.00.00.00.00.0

srt:ProvedUndevelopedReserveVolume us-gaap:Energy, us-gaap:StatementGeographical

srt:NaturalGasPerThousandCubicFeet, nfg:AppalachianRegion


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value0.5512621.0147240.750810.6100180.541959
Percentage of ProvedUndevelopedReserveVolume0.00.00.00.00.0

srt:ProvedUndevelopedReserveVolume us-gaap:StatementGeographical

nfg:MarcellusShaleFields


Proved
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value287000383000394000456000542000
Percentage of ProvedUndevelopedReserveVolume52.137.652.074.599.8

nfg:UticaShale


Proved
Period End2020-09-302019-09-302018-09-302017-09-30
Value265000632000357000154000
Percentage of ProvedUndevelopedReserveVolume48.162.147.225.2

srt:StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves

srt:StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves


Standardized
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value12221736172011136421323
Percentage of StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves100.0100.0100.0100.0100.0100.0

us-gaap:AccountsAndOtherReceivablesNetCurrent

us-gaap:AccountsAndOtherReceivablesNetCurrent


Accounts
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-09-30
Value188229178143136172139
Percentage of AccountsAndOtherReceivablesNetCurrent100.0100.0100.0100.0100.0100.0100.0

us-gaap:AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax us-gaap:StatementBusinessSegments

us-gaap:AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax

nfg:AccumulatedLosses


Accumulated
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-30
Value8985455775685656100
Percentage of AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivable

us-gaap:AllowanceForDoubtfulAccountsReceivable


Allowance
Period End2021-06-302021-03-312020-12-312020-09-30
Value320.0301280.0262210.02281
Percentage of AllowanceForDoubtfulAccountsReceivable100.0100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent


Allowance
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
Value3230262226292625293026242628242227272221273430293440353136383127343834303843353139443530
Percentage of AllowanceForDoubtfulAccountsReceivableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AociLossCashFlowHedgeCumulativeGainLossAfterTax

us-gaap:AociLossCashFlowHedgeCumulativeGainLossAfterTax


Aoci
Period End2021-06-302021-03-312020-12-312020-09-30
Value-148.6-12.11024
Percentage of AociLossCashFlowHedgeCumulativeGainLossAfterTax100.0100.0100.0100.0

us-gaap:AssetRetirementObligation

us-gaap:AssetRetirementObligation


Asset
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302016-06-302015-09-302014-09-302013-09-302012-09-302011-09-302010-09-302009-09-302008-09-30
Value192127108106112114156117119119751019193
Percentage of AssetRetirementObligation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AssetRetirementObligationsNoncurrent

us-gaap:AssetRetirementObligationsNoncurrent


Asset
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
Value1911921921921281281281271041041041081011061061061151141131121141711581561191191181171211201201191261251231197877767565102100101
Percentage of AssetRetirementObligationsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AssetsHeldForSaleNotPartOfDisposalGroup

us-gaap:AssetsHeldForSaleNotPartOfDisposalGroup


Assets
Period End2020-09-30
Value53
Percentage of AssetsHeldForSaleNotPartOfDisposalGroup100.0

us-gaap:CapitalizationLongtermDebtAndEquity

us-gaap:CapitalizationLongtermDebtAndEquity


Capitalization
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
Value46384726417546014854421443164272427642224178406837624004394437873472373836553613361337073897410943464248425240593989394838993843378636913165310931383115332027902749271526532794
Percentage of CapitalizationLongtermDebtAndEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CapitalizedCostsAccumulatedDepreciationDepletionAmortizationAndValuationAllowanceForRelatingToOilAndGasProducingActivities

us-gaap:CapitalizedCostsAccumulatedDepreciationDepletionAmortizationAndValuationAllowanceForRelatingToOilAndGasProducingActivities


Capitalized
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-302010-09-30
Value46284012386237653657257212119196814991094
Percentage of CapitalizedCostsAccumulatedDepreciationDepletionAmortizationAndValuationAllowanceForRelatingToOilAndGasProducingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CapitalizedCostsAssetRetirementCosts

us-gaap:CapitalizedCostsAssetRetirementCosts


Capitalized
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-302010-09-30
Value132704454631137580433269
Percentage of CapitalizedCostsAssetRetirementCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CapitalizedCostsOilAndGasProducingActivitiesGross

us-gaap:CapitalizedCostsOilAndGasProducingActivitiesGross


Capitalized
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-302010-09-30
Value63865677517649134690465040823499293522362418
Percentage of CapitalizedCostsOilAndGasProducingActivitiesGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CapitalizedCostsOilAndGasProducingActivitiesNet

us-gaap:CapitalizedCostsOilAndGasProducingActivitiesNet


Capitalized
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-302010-09-30
Value18001800170018001600160017001700131411471032207728712579225317371323
Percentage of CapitalizedCostsOilAndGasProducingActivitiesNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CapitalizedCostsProvedProperties

us-gaap:CapitalizedCostsProvedProperties


Capitalized
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-302010-09-30
Value62385623511448324554447339413393278920102267
Percentage of CapitalizedCostsProvedProperties100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CapitalizedCostsUnprovedProperties

us-gaap:CapitalizedCostsUnprovedProperties


Capitalized
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-302010-09-30
Value148536280135176141106146226151
Percentage of CapitalizedCostsUnprovedProperties100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashAndCashEquivalentsFairValueDisclosure

us-gaap:CashAndCashEquivalentsFairValueDisclosure


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-09-30
Value1046689125409520107579862152911961325272572141191138165109228546202386129165112287334611716232
Percentage of CashAndCashEquivalentsFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashAndCashEquivalentsFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueInputsLevel1


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-09-30
Value1046689125409520107579862152911961325272572141191138165109228546202386129165112287334611716232
Percentage of CashAndCashEquivalentsFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashSurrenderValueOfLifeInsurance

us-gaap:CashSurrenderValueOfLifeInsurance


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-09-30
Value444342414141414140403939393938394140393939384545454444444443575757565657565554545455
Percentage of CashSurrenderValueOfLifeInsurance100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CommercialPaperAtCarryingValue

us-gaap:CommercialPaperAtCarryingValue


Commercial
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-30
Value15550.00.00.00.0850.016540
Percentage of CommercialPaperAtCarryingValue100.0100.00.00.00.00.0100.00.0100.0100.0

us-gaap:CommonStockValueOutstanding us-gaap:StatementEquityComponents

us-gaap:CommonStockValueOutstanding

us-gaap:CommonStock


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-09-302015-09-302014-09-302013-09-302012-09-302011-09-302010-09-302009-09-302008-09-30
Value91919190908686868686868585858585858484838382828079
Percentage of CommonStockValueOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ContractualObligationDueAfterFifthYear us-gaap:StatementBusinessSegments

us-gaap:ContractualObligationDueAfterFifthYear

nfg:PipelineAndStorageGatheringAndUtilitySegments


Contractual
Period End2020-09-30
Value10
Percentage of ContractualObligationDueAfterFifthYear100.0

us-gaap:ContractualObligationDueInFifthYear us-gaap:StatementBusinessSegments

us-gaap:ContractualObligationDueInFifthYear

nfg:PipelineAndStorageGatheringAndUtilitySegments


Contractual
Period End2020-09-30
Value3300000.0
Percentage of ContractualObligationDueInFifthYear100.0

us-gaap:ContractualObligationDueInFourthYear us-gaap:StatementBusinessSegments

us-gaap:ContractualObligationDueInFourthYear

nfg:PipelineAndStorageGatheringAndUtilitySegments


Contractual
Period End2020-09-30
Value3300000.0
Percentage of ContractualObligationDueInFourthYear100.0

us-gaap:ContractualObligationDueInNextTwelveMonths us-gaap:StatementBusinessSegments

us-gaap:ContractualObligationDueInNextTwelveMonths

nfg:ExplorationAndProduction


Contractual
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-30
Value1091048679251049513
Percentage of ContractualObligationDueInNextTwelveMonths100.0100.0100.0100.0100.0100.0100.0100.0

nfg:PipelineAndStorageGatheringAndUtilitySegments


Contractual
Period End2020-09-302019-09-302018-09-302017-09-30
Value989710561
Percentage of ContractualObligationDueInNextTwelveMonths89.993.5121.977.6

us-gaap:ContractualObligationDueInSecondYear us-gaap:StatementBusinessSegments

us-gaap:ContractualObligationDueInSecondYear

nfg:ExplorationAndProduction


Contractual
Period End2020-09-302019-09-302018-09-302017-09-302015-09-302014-09-302013-09-30
Value1522249825240.2
Percentage of ContractualObligationDueInSecondYear100.0100.0100.0100.0100.0100.0100.0

nfg:PipelineAndStorageGatheringAndUtilitySegments


Contractual
Period End2020-09-302019-09-302018-09-302017-09-30
Value6.4346.80.7
Percentage of ContractualObligationDueInSecondYear42.1157.227.40.7

us-gaap:ContractualObligationDueInThirdYear us-gaap:StatementBusinessSegments

us-gaap:ContractualObligationDueInThirdYear

nfg:ExplorationAndProduction


Contractual
Period End2020-09-302019-09-302017-09-302013-09-30
Value0.71.7170.2
Percentage of ContractualObligationDueInThirdYear100.0100.0100.0100.0

nfg:PipelineAndStorageGatheringAndUtilitySegments


Contractual
Period End2020-09-302019-09-302017-09-30
Value3.46.00.2
Percentage of ContractualObligationDueInThirdYear485.7352.91.2

us-gaap:CreditRiskDerivativeAssetsAtFairValue

us-gaap:CreditRiskDerivativeAssetsAtFairValue


Credit
Period End2021-03-312020-12-312020-09-30
Value1.5148.6
Percentage of CreditRiskDerivativeAssetsAtFairValue100.0100.0100.0

us-gaap:CreditRiskDerivativeAssetsAtFairValue nfg:CreditRiskExposure

nfg:LessThan100000


Credit
Period End2021-06-30
Value0.1
Percentage of CreditRiskDerivativeAssetsAtFairValue0.0

us-gaap:CreditRiskDerivativeLiabilitiesAtFairValue

us-gaap:CreditRiskDerivativeLiabilitiesAtFairValue


Credit
Period End2021-06-302021-03-312020-12-312020-09-30
Value190214.544
Percentage of CreditRiskDerivativeLiabilitiesAtFairValue100.0100.0100.0100.0

us-gaap:DebtInstrumentCarryingAmount us-gaap:LongtermDebtType

us-gaap:DebtInstrumentCarryingAmount

nfg:IndentureFrom1974


Debt
Period End2020-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-30
Value9999989899999999
Percentage of DebtInstrumentCarryingAmount100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DebtInstrumentFaceAmount us-gaap:LongtermDebtType

us-gaap:DebtInstrumentFaceAmount

nfg:FourPointNinePercentNotesDueDecemberFirstTwoThousandTwentyOne


Debt
Period End2020-09-30
Value500
Percentage of DebtInstrumentFaceAmount100.0

nfg:FourPointNinePercentNotesDueDecemberOneTwoThousandTwentyOne


Debt
Period End2021-03-11
Value500
Percentage of DebtInstrumentFaceAmount0.0

nfg:TwoPointNineFivePercentNotesDueMarchFirstTwoThousandThirtyOne


Debt
Period End2021-02-24
Value500
Percentage of DebtInstrumentFaceAmount0.0

us-gaap:DebtInstrumentFairValue

us-gaap:DebtInstrumentFairValue


Debt
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-09-30
Value291328692868277827131948225322572252219221142121211621692214252322202221222922552207202619702129216217941751177517981787174917671790187116171623159515541536119812091423
Percentage of DebtInstrumentFairValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet

us-gaap:DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet


Debt
Period End2020-09-302019-09-302018-09-302017-09-302016-09-30
Value1915171512
Percentage of DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet100.0100.0100.0100.0100.0

us-gaap:DebtInstrumentUnusedBorrowingCapacityAmount

us-gaap:DebtInstrumentUnusedBorrowingCapacityAmount


Debt
Period End2020-09-30
Value1300
Percentage of DebtInstrumentUnusedBorrowingCapacityAmount100.0

us-gaap:DeferredCosts

us-gaap:DeferredCosts


Deferred
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-09-30
Value58606167875656333339424037363430282622201717161512101214109.059.8189.3828.0517.591
Percentage of DeferredCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredCreditsAndOtherLiabilitiesNoncurrent

us-gaap:DeferredCreditsAndOtherLiabilitiesNoncurrent


Deferred
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302018-09-30
Value139141145139137134140122114111
Percentage of DeferredCreditsAndOtherLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsCapitalLossCarryforwards

us-gaap:DeferredTaxAssetsCapitalLossCarryforwards


Deferred
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-09-30
Value179175214200194185171160184197215194188192198107998371549.772
Percentage of DeferredTaxAssetsCapitalLossCarryforwards100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsCharitableContributionCarryforwards

us-gaap:DeferredTaxAssetsCharitableContributionCarryforwards


Deferred
Period End2020-09-30
Value1559000.0
Percentage of DeferredTaxAssetsCharitableContributionCarryforwards100.0

us-gaap:DeferredTaxAssetsGross

us-gaap:DeferredTaxAssetsGross


Deferred
Period End2020-09-302019-09-302018-09-302017-09-30
Value319318352406
Percentage of DeferredTaxAssetsGross100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsOperatingLossCarryforwardsNotSubjectToExpiration us-gaap:IncomeTaxAuthority

us-gaap:DeferredTaxAssetsOperatingLossCarryforwardsNotSubjectToExpiration

us-gaap:InternalRevenueServiceIRS


Deferred
Period End2020-09-30
Value185
Percentage of DeferredTaxAssetsOperatingLossCarryforwardsNotSubjectToExpiration100.0

us-gaap:DeferredTaxAssetsOperatingLossCarryforwardsSubjectToExpiration us-gaap:IncomeTaxAuthority

us-gaap:DeferredTaxAssetsOperatingLossCarryforwardsSubjectToExpiration

us-gaap:InternalRevenueServiceIRS


Deferred
Period End2020-09-30
Value205
Percentage of DeferredTaxAssetsOperatingLossCarryforwardsSubjectToExpiration100.0

us-gaap:DeferredTaxAssetsOther

us-gaap:DeferredTaxAssetsOther


Deferred
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-09-30
Value445575829211010310299899081948383817875748081
Percentage of DeferredTaxAssetsOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxLiabilitiesOther

us-gaap:DeferredTaxLiabilitiesOther


Deferred
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-09-30
Value235449575551875555727564385243686867703863
Percentage of DeferredTaxLiabilitiesOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment


Deferred
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-09-30
Value87486177011411049129116141584155115171504146514271365133312271185111610621035849
Percentage of DeferredTaxLiabilitiesPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAccumulatedBenefitObligation us-gaap:RetirementPlanTaxStatus

us-gaap:DefinedBenefitPlanAccumulatedBenefitObligation

us-gaap:NonqualifiedPlan


Defined
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value787970727266
Percentage of DefinedBenefitPlanAccumulatedBenefitObligation100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAccumulatedBenefitObligation us-gaap:RetirementPlanType

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value1096105394610101039968
Percentage of DefinedBenefitPlanAccumulatedBenefitObligation1393.21320.71341.01393.41435.61468.2

us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditAfterTax

us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditAfterTax


Defined
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-302013-09-302012-09-30
Value900000.01000000.01000000.01200000.01300000.01500000.0200000.0300000.0400000.0
Percentage of DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditAfterTax100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent

us-gaap:DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302012-09-30
Value93898076757164608886848261595756181817172726252446433936292824220.0
Percentage of DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent us-gaap:RetirementPlanType

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value766082561724
Percentage of DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate us-gaap:RetirementPlanTaxStatus

us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate

us-gaap:NonqualifiedPlan


Defined
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value1.920.02770.04020.03220.0280.035
Percentage of DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate us-gaap:RetirementPlanType

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value2.710.03170.04310.03810.0370.045
Percentage of DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate141.1114.4107.2118.3132.1128.6

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value2.660.03150.0430.03770.0360.0425
Percentage of DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate138.5113.7107.0117.1128.6121.4

us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease us-gaap:RetirementPlanTaxStatus

us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease

us-gaap:NonqualifiedPlan


Defined
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value8.00.080.07750.07750.07750.0775
Percentage of DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease us-gaap:RetirementPlanType

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value4.70.0470.0470.0470.0470.0475
Percentage of DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease58.858.860.660.660.661.3

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value4.70.0470.0470.0470.0470.0475
Percentage of DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease58.858.860.660.660.661.3

us-gaap:DefinedBenefitPlanBenefitObligation us-gaap:BalanceSheetLocation, us-gaap:RetirementPlanTaxStatus

us-gaap:DefinedBenefitPlanBenefitObligation

nfg:Current, us-gaap:NonqualifiedPlan


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302018-09-302017-09-302016-09-302015-09-30
Value141414141313131311149.84.5
Percentage of DefinedBenefitPlanBenefitObligation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

nfg:NonCurrent, us-gaap:NonqualifiedPlan


Defined
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value838674748181
Percentage of DefinedBenefitPlanBenefitObligation578.1654.1648.7530.5835.71806.7

us-gaap:DefinedBenefitPlanBenefitObligation us-gaap:RetirementPlanTaxStatus

us-gaap:NonqualifiedPlan


Defined
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value989986889185
Percentage of DefinedBenefitPlanBenefitObligation678.4754.1748.7630.5935.71906.7

us-gaap:DefinedBenefitPlanBenefitObligation us-gaap:RetirementPlanType

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-30
Value476468435462526464465
Percentage of DefinedBenefitPlanBenefitObligation3296.83548.33791.23281.05368.810333.00.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-302014-09-30
Value11391097985105410971026999
Percentage of DefinedBenefitPlanBenefitObligation7877.68319.18571.27481.011198.222804.20.0

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-30
Value143147153152
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value326328
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter227.4223.4

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-30
Value28272726
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value6666
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths235.5236.8

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-30
Value29293029
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value6767
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive229.6226.5

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-30
Value29292929
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value6767
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour230.9227.6

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-30
Value29292928
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value6767
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree231.7230.3

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-30
Value28282827
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value6766
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo233.2232.7

us-gaap:DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear us-gaap:Range, us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear

srt:Maximum, nfg:VebaTrusts


Defined
Period End2020-09-302019-09-302018-09-30
Value3.03.04.0
Percentage of DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear100.0100.0100.0

srt:Maximum, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-30
Value253035
Percentage of DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear833.31000.0875.0

srt:Minimum, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-30
Value152529
Percentage of DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear500.0833.3725.0

us-gaap:DefinedBenefitPlanExpectedFutureEmployerContributionsRemainderOfFiscalYear us-gaap:Range, us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureEmployerContributionsRemainderOfFiscalYear

srt:Maximum, nfg:VebaTrusts


Defined
Period End2021-03-312020-12-312020-03-312019-12-312019-03-312018-12-31
Value1.02.51.02.51.03.0
Percentage of DefinedBenefitPlanExpectedFutureEmployerContributionsRemainderOfFiscalYear100.0100.0100.0100.0100.0100.0

srt:Maximum, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-03-312020-12-312020-06-302020-03-312019-12-312019-06-302019-03-312018-12-312018-06-30
Value10.0206.010.0225.05.05.05.0
Percentage of DefinedBenefitPlanExpectedFutureEmployerContributionsRemainderOfFiscalYear1000.0800.00.01000.0880.00.0500.0166.70.0

srt:Minimum, nfg:VebaTrusts


Defined
Period End2021-03-312020-12-312020-03-312019-12-312019-03-312018-12-31
Value0.52.00.52.00.52.0
Percentage of DefinedBenefitPlanExpectedFutureEmployerContributionsRemainderOfFiscalYear50.080.050.080.050.066.7

srt:Minimum, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-03-312020-12-312020-06-302020-03-312019-12-31
Value5.010.01.05.017
Percentage of DefinedBenefitPlanExpectedFutureEmployerContributionsRemainderOfFiscalYear500.0400.00.0500.0680.0

us-gaap:DefinedBenefitPlanExpectedFutureEmployerContributionsRemainderOfFiscalYear us-gaap:RetirementPlanType

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-30
Value1.1
Percentage of DefinedBenefitPlanExpectedFutureEmployerContributionsRemainderOfFiscalYear0.0

us-gaap:DefinedBenefitPlanFundedStatusOfPlan us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanFundedStatusOfPlan

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value71557751-31.81812
Percentage of DefinedBenefitPlanFundedStatusOfPlan100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value-122.309-129.176-61.184-144.107-227.646-191.32
Percentage of DefinedBenefitPlanFundedStatusOfPlan-171.9-230.8-78.6-280.4715.5-1474.9

us-gaap:DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount

nfg:RetirementPlanInvestment, us-gaap:FairValueInputsLevel1, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value120116
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount100.0100.0

nfg:RetirementPlanInvestment, us-gaap:FairValueInputsLevel2, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value477456
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount397.6393.6

nfg:RetirementPlanInvestment, us-gaap:FairValueInputsLevel3, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value0.4713.154
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount0.42.7

nfg:RetirementPlanInvestment, us-gaap:FairValueMeasuredAtNetAssetValuePerShare, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value499464
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount416.1399.9

nfg:TotalInvestmentsIncluding401hInvestments, us-gaap:FairValueInputsLevel1, us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value310283
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount258.1244.2

nfg:TotalInvestmentsIncluding401hInvestments, us-gaap:FairValueInputsLevel2, us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value3532
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount29.227.8

nfg:TotalInvestmentsIncluding401hInvestments, us-gaap:FairValueInputsLevel3, us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value0.0350.223
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount0.00.2

nfg:TotalInvestmentsIncluding401hInvestments, us-gaap:FairValueMeasuredAtNetAssetValuePerShare, us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value204209
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount170.2180.1

nfg:TotalRetirementPlanInvestmentsExcluding401HInvestments, us-gaap:FairValueInputsLevel1, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value111107
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount92.792.9

nfg:TotalRetirementPlanInvestmentsExcluding401HInvestments, us-gaap:FairValueInputsLevel2, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value442424
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount368.4365.8

nfg:TotalRetirementPlanInvestmentsExcluding401HInvestments, us-gaap:FairValueInputsLevel3, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value0.4362.931
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount0.42.5

nfg:TotalRetirementPlanInvestmentsExcluding401HInvestments, us-gaap:FairValueMeasuredAtNetAssetValuePerShare, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value463431
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount385.5371.5

nfg:TotalVebaTrustInvestments, us-gaap:FairValueInputsLevel1, us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value301275
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount250.8237.1

nfg:TotalVebaTrustInvestments, us-gaap:FairValueMeasuredAtNetAssetValuePerShare, us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value167176
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount139.7151.8

us-gaap:DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:RetirementPlanType

nfg:RetirementPlanInvestment, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value10971040
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount914.0896.2

nfg:TotalInvestmentsIncluding401hInvestments, us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value549525
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount457.5452.3

nfg:TotalRetirementPlanInvestmentsExcluding401HInvestments, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value1017966
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount847.0832.7

nfg:TotalVebaTrustInvestments, us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302019-09-30
Value469451
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount390.5388.9

us-gaap:DefinedBenefitPlanPlanAssetsTargetAllocationPercentage us-gaap:Range, us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanPlanAssetsTargetAllocationPercentage

srt:Maximum, nfg:OtherSecurities, nfg:RetirementPlanandVebaTrustsAnd401HAccounts


Defined
Period End2020-09-302019-09-302018-09-30
Value15.00.150.15
Percentage of DefinedBenefitPlanPlanAssetsTargetAllocationPercentage100.0100.0100.0

srt:Maximum, us-gaap:EquitySecurities, nfg:RetirementPlanandVebaTrustsAnd401HAccounts


Defined
Period End2020-09-302019-09-302018-09-30
Value50.00.50.5
Percentage of DefinedBenefitPlanPlanAssetsTargetAllocationPercentage333.3333.3333.3

srt:Maximum, us-gaap:FixedIncomeFunds, nfg:RetirementPlanandVebaTrustsAnd401HAccounts


Defined
Period End2020-09-302019-09-302018-09-30
Value70.00.70.7
Percentage of DefinedBenefitPlanPlanAssetsTargetAllocationPercentage466.7466.7466.7

srt:Minimum, us-gaap:EquitySecurities, nfg:RetirementPlanandVebaTrustsAnd401HAccounts


Defined
Period End2020-09-302019-09-302018-09-30
Value30.00.30.3
Percentage of DefinedBenefitPlanPlanAssetsTargetAllocationPercentage200.0200.0200.0

srt:Minimum, us-gaap:FixedIncomeFunds, nfg:RetirementPlanandVebaTrustsAnd401HAccounts


Defined
Period End2020-09-302019-09-302018-09-30
Value50.00.50.5
Percentage of DefinedBenefitPlanPlanAssetsTargetAllocationPercentage333.3333.3333.3

us-gaap:DefinedBenefitPlanUltimateHealthCareCostTrendRate1

us-gaap:DefinedBenefitPlanUltimateHealthCareCostTrendRate1


Defined
Period End2020-09-302019-09-302018-09-302017-09-302016-09-302015-09-30
Value4.50.0450.0450.0450.0450.045
Percentage of DefinedBenefitPlanUltimateHealthCareCostTrendRate1100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeAssets us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:InvestmentType

us-gaap:DerivativeAssets

us-gaap:FairValueInputsLevel2, nfg:OverCounterSwapsGasAndOil


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-30
Value5.35118373683103465244234326283230386773621191372552842722402972887556487657
Percentage of DerivativeAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueInputsLevel2, us-gaap:ForeignExchangeContract


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-12-312015-09-30
Value1.8351.4371.0270.2590.1070.00.1180.0050.0780.0050.00.4430.1550.6081.2321.2270.3360.0480.00.00.00.00.0
Percentage of DerivativeAssets34.37.62.70.70.10.00.30.00.20.00.01.70.61.94.03.10.50.10.00.00.00.00.0

us-gaap:DerivativeAssets us-gaap:FairValueConcentrationOfRiskDisclosureItems, us-gaap:InvestmentType

us-gaap:FairValueConcentrationOfCreditRiskMasterNettingArrangements, nfg:OverCounterNoCostCollarsGasAndOil


Derivative
Period End2020-09-30
Value-0.72
Percentage of DerivativeAssets-2.0

us-gaap:FairValueConcentrationOfCreditRiskMasterNettingArrangements, nfg:OverCounterSwapsGasAndOil


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-3