SYNH


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

Table of contents



us-gaap:CommonStockValue

us-gaap:CommonStockSharesIssued

us-gaap:CommonStockSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareDiluted
us-gaap:ConsolidationItems, us-gaap:IncomeStatementLocation
us-gaap:AllocatedShareBasedCompensationExpense

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:CostOfGoodsAndServicesSold
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:CostOfRevenue

us-gaap:CostsAndExpenses

us-gaap:GainsLossesOnExtinguishmentOfDebt
us-gaap:LongtermDebtType

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest

us-gaap:IncomeTaxExpenseBenefit

us-gaap:InterestExpense

us-gaap:NetIncomeLoss
us-gaap:StatementEquityComponents

us-gaap:NonoperatingIncomeExpense

us-gaap:OperatingIncomeLoss
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:StatementEquityComponents
us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax

us-gaap:OtherNonoperatingIncomeExpense

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:StatementGeographical

us-gaap:SellingGeneralAndAdministrativeExpense
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:Assets

us-gaap:Liabilities

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:StockholdersEquity
us-gaap:StatementEquityComponents

us-gaap:AssetsCurrent
us-gaap:ConcentrationRiskByType, us-gaap:GeographicDistribution
us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:PrepaidExpenseAndOtherAssetsCurrent

us-gaap:PropertyPlantAndEquipmentGross
us-gaap:PropertyPlantAndEquipmentByType

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment

us-gaap:AmortizationOfIntangibleAssets

us-gaap:PropertyPlantAndEquipmentNet
us-gaap:StatementGeographical

us-gaap:Goodwill
us-gaap:BusinessAcquisition
us-gaap:BusinessAcquisition, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments

us-gaap:IntangibleAssetsNetExcludingGoodwill

us-gaap:FiniteLivedIntangibleAssetsNet
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:FairValueByMeasurementFrequency
us-gaap:IntangibleAssetsNetIncludingGoodwill

us-gaap:DeferredTaxAssetsLiabilitiesNet

us-gaap:OperatingLeaseRightOfUseAsset

us-gaap:OtherAssetsNoncurrent

us-gaap:AccountsPayableCurrent

us-gaap:AccruedLiabilitiesCurrent

us-gaap:ContractWithCustomerLiabilityCurrent

us-gaap:LiabilitiesCurrent

us-gaap:LongTermDebtCurrent

us-gaap:OperatingLeaseLiabilityCurrent

us-gaap:OtherAccruedLiabilitiesCurrent

us-gaap:TaxesPayableCurrent

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

us-gaap:LongTermDebtNoncurrent

us-gaap:DeferredIncomeTaxLiabilitiesNet

us-gaap:OtherLiabilitiesNoncurrent

us-gaap:OperatingLeaseLiabilityNoncurrent

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive

us-gaap:OperatingLeaseLiability

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:StockholdersEquity
us-gaap:StatementEquityComponents

us-gaap:CommonStockValue

us-gaap:AdditionalPaidInCapital

us-gaap:RetainedEarningsAccumulatedDeficit

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

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:AmortizationOfFinancingCosts

us-gaap:DeferredIncomeTaxExpenseBenefit

us-gaap:DepreciationDepletionAndAmortization

us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetIncomeLoss
us-gaap:StatementEquityComponents

us-gaap:ShareBasedCompensation

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:RepaymentsOfLongTermDebt
us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:PaymentsForRepurchaseOfCommonStock
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentInterestRateStatedPercentage
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice

us-gaap:DeferredTaxAssetsNet

us-gaap:UnrecognizedTaxBenefits

us-gaap:DeferredTaxAssetsValuationAllowance

synh:AssetsExchangedInCash
us-gaap:ValuationAllowancesAndReservesType
synh:BusinessExitCostsAndGainLossOnTerminationOfLease
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
synh:DebtInstrumentCovenantFirstLienLeverageRatioMaximum

synh:IncomeTaxesDiscreteTaxExpenseBenefits

synh:IncreaseDecreaseInAccountsReceivableContractWithCustomerAssetNetCurrentAndContractWithCustomerLiabilityCurrent

synh:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTaxPortionAttributableToParent1

synh:OtherSundryNonoperatingIncomeExpense

synh:ProceedsFromInvestmentsInUnconsolidatedAffiliates

synh:RestructuringChargeIncludingOtherCosts
us-gaap:ConsolidationItems
us-gaap:RestructuringCostAndReserve, us-gaap:ValuationAllowancesAndReservesType
synh:RestructuringChargeIncludingOtherCosts1
us-gaap:ValuationAllowancesAndReservesType
us-gaap:StatementClassOfStock
synh:StockRepurchaseProgramSharesPurchasedValue

synh:TradeReceivablesSold

synh:TransactionAndIntegrationRelatedCosts
us-gaap:ConsolidationItems
us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationConsiderationTransferred1

us-gaap:BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationAsset1

us-gaap:BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1

us-gaap:BusinessCombinationIntegrationRelatedCosts
us-gaap:BusinessAcquisition
us-gaap:CashAcquiredFromAcquisition
us-gaap:ConcentrationRiskByBenchmark, us-gaap:ConcentrationRiskByType
us-gaap:ConcentrationRiskPercentage1
us-gaap:StatementGeographical, us-gaap:ConcentrationRiskByBenchmark, us-gaap:ConcentrationRiskByType

us-gaap:ContractWithCustomerLiabilityRevenueRecognized

us-gaap:ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod
us-gaap:ConsolidatedEntities, us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:VariableRate
us-gaap:DebtInstrumentBasisSpreadOnVariableRate1
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentPeriodicPaymentPrincipal

us-gaap:Depreciation
us-gaap:ConsolidationItems
us-gaap:DepreciationAmortizationAndAccretionNet

us-gaap:EarlyRepaymentOfSeniorDebt

us-gaap:EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements

us-gaap:FairValueOfAssetsAcquired
us-gaap:BusinessAcquisition
us-gaap:FinitelivedIntangibleAssetsAcquired1
us-gaap:BusinessAcquisition, us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:ForeignCurrencyTransactionGainLossBeforeTax

us-gaap:ForeignCurrencyTransactionGainLossRealized
us-gaap:DerivativeInstrumentRisk

us-gaap:ForeignCurrencyTransactionGainLossUnrealized
us-gaap:StatementBusinessSegments
us-gaap:GainLossOnSaleOfBusiness

us-gaap:GoodwillForeignCurrencyTranslationGainLoss
us-gaap:StatementBusinessSegments

us-gaap:GoodwillPurchaseAccountingAdjustments
us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments
us-gaap:GoodwillTransfers

us-gaap:IncomeLossFromEquityMethodInvestments

us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

us-gaap:InterestAndOtherIncome

us-gaap:LineOfCreditFacilityDecreaseForgiveness1
us-gaap:DebtInstrument
us-gaap:StatementBusinessSegments
us-gaap:NoncashOrPartNoncashDivestitureAmountOfConsiderationReceived1
us-gaap:StatementEquityComponents
us-gaap:OciBeforeReclassificationsBeforeTaxAttributableToParent

us-gaap:OciBeforeReclassificationsNetOfTaxAttributableToParent
us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent
us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsTax
us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax

us-gaap:OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax
us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
us-gaap:StatementEquityComponents

us-gaap:OtherNoncashIncomeExpense

us-gaap:PaymentForContingentConsiderationLiabilityFinancingActivities

us-gaap:PaymentsOfDebtIssuanceCosts

us-gaap:PaymentsRelatedToTaxWithholdingForShareBasedCompensation

us-gaap:PaymentsToAcquireBusinessesNetOfCashAcquired
us-gaap:BusinessAcquisition
us-gaap:BusinessAcquisition, us-gaap:SubsequentEventType

us-gaap:PaymentsToAcquireInterestInSubsidiariesAndAffiliates

us-gaap:ProceedsFromAccountsReceivableSecuritization

us-gaap:ProceedsFromDivestitureOfBusinesses
us-gaap:StatementBusinessSegments

us-gaap:ProceedsFromLinesOfCredit

us-gaap:ProceedsFromSaleAndCollectionOfReceivables
us-gaap:StatementBusinessSegments
us-gaap:ProceedsFromSaleOfNotesReceivable

us-gaap:ProceedsFromStockOptionsExercised

us-gaap:ProfessionalFees

us-gaap:ProvisionForDoubtfulAccounts
us-gaap:StatementEquityComponents
us-gaap:ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent
us-gaap:StatementEquityComponents
us-gaap:ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent
us-gaap:StatementEquityComponents
us-gaap:ReclassificationFromAociCurrentPeriodTax

us-gaap:RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty
us-gaap:TitleOfIndividual
us-gaap:RelatedPartyTransactionPurchasesFromRelatedParty

us-gaap:RepaymentsOfAccountsReceivableSecuritization

us-gaap:RepaymentsOfLinesOfCredit

us-gaap:RepaymentsOfLongTermCapitalLeaseObligations

us-gaap:RestructuringAndRelatedCostIncurredCost
us-gaap:BusinessAcquisition, us-gaap:RestructuringCostAndReserve
us-gaap:RestructuringCostAndReserve

us-gaap:RevenueFromRelatedParties
us-gaap:StatementClassOfStock
us-gaap:StockRepurchasedDuringPeriodValue
us-gaap:StatementEquityComponents
us-gaap:StatementClassOfStock
us-gaap:TreasuryStockAcquiredAverageCostPerShare
us-gaap:IncomeTaxAuthority
us-gaap:UnrecognizedTaxBenefitsPeriodIncreaseDecrease

us-gaap:UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations
us-gaap:RestructuringCostAndReserve, us-gaap:ValuationAllowancesAndReservesType
us-gaap:ValuationAllowancesAndReservesChargedToCostAndExpense
us-gaap:ValuationAllowancesAndReservesType
us-gaap:RestructuringCostAndReserve, us-gaap:ValuationAllowancesAndReservesType
us-gaap:ValuationAllowancesAndReservesDeductions
us-gaap:ValuationAllowancesAndReservesType

synh:AccruedRebatesToCustomersCurrent
us-gaap:BusinessAcquisition
synh:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccountsPayableAndAccruedExpenses
us-gaap:BusinessAcquisition
synh:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedContractWithCustomerLiability
us-gaap:BusinessAcquisition
synh:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsAccountsReceivableAndUnbilledServices
us-gaap:BusinessAcquisition
synh:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightOfUseAssets

synh:BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedCurrentTaxSharingObligation

synh:CashandCashEquivalentsCashPoolingAgreementCashPoolBorrowings

synh:CashandCashEquivalentsCashPoolingAgreementGrossCashPosition

synh:CashandCashEquivalentsCashPoolingAgreementNetCashPosition

synh:ContractualObligationNotYetSatisfied

synh:DeferredTaxAssetInterestLimitationCarryforward

synh:DeferredTaxAssetsTaxDeferredExpenseLeaseObligations

synh:DeferredTaxAssetsTaxDeferredExpensePrepaidRoyalty

synh:DeferredTaxLiabilitiesRightOfUseAssets

synh:FinanceLeaseLiabilityManagementFee

synh:FinanceLeaseRightOfUseAssetAccumulatedDepreciation

synh:ForeignEarningsPreviouslyTaxedintheUSIntendedToBePermanentlyReinvested

synh:ForeignEarningsPreviouslyTaxedintheUSIntendedToBeRepatriated

synh:ForeignEarningsPreviouslyTaxedintheUSTotal

synh:LongTermDebtMaturitiesRepaymentsOfInterestInYearFive

synh:LongTermDebtMaturitiesRepaymentsOfInterestInYearFour

synh:LongTermDebtMaturitiesRepaymentsOfInterestInYearThree

synh:LongTermDebtMaturitiesRepaymentsOfInterestInYearTwo

synh:LongTermDebtMaturitiesRepaymentsOfInterestRemainderOfFiscalYear

synh:LongTermDebtRepaymentsOfInterest

synh:OperatingAndFinanceLeaseLiabilityPaymentsDue

synh:OperatingAndFinanceLeaseLiabilityPaymentsDueAfterYearFive

synh:OperatingAndFinanceLeaseLiabilityPaymentsDueYearFive

synh:OperatingAndFinanceLeaseLiabilityPaymentsDueYearFour

synh:OperatingAndFinanceLeaseLiabilityPaymentsDueYearThree

synh:OperatingAndFinanceLeaseLiabilityPaymentsDueYearTwo

synh:OperatingAndFinanceLeaseLiabilityPaymentsNextTwelveMonths
us-gaap:ConcentrationRiskByType, us-gaap:GeographicDistribution
synh:PercentageOfCashAndCashEquivalentsBalanceConsolidated
us-gaap:BusinessAcquisition
synh:PercentageOfOutstandingSharesPurchase
us-gaap:SubsequentEventType

synh:ReceivablesNetCurrentAndContractWithCustomerAssetNetCurrent

synh:StockholdersEquityAttributableToParentAdjustedBalance
us-gaap:StatementEquityComponents

us-gaap:AccountsReceivableGrossCurrent

us-gaap:AccruedProfessionalFeesCurrent

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency, us-gaap:InvestmentType
us-gaap:AlternativeInvestment
us-gaap:FairValueByMeasurementFrequency, us-gaap:InvestmentType
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:AssetsFairValueDisclosure
us-gaap:FairValueByMeasurementFrequency
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:BusinessCombinationContingentConsiderationAsset
us-gaap:StatementBusinessSegments
us-gaap:BusinessAcquisition, us-gaap:FairValueByMeasurementFrequency
us-gaap:BusinessCombinationContingentConsiderationLiability
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency
us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets
us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligation
us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents
us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets
us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities
us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill
us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles
us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities
us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet
us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther
us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets
us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment

us-gaap:CapitalLeaseObligationsCurrent

us-gaap:ContractWithCustomerAssetNetCurrent
us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentCarryingAmount
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:LongtermDebtType
us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentFaceAmount
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentUnamortizedDiscount

us-gaap:DebtInstrumentUnamortizedDiscountPremiumNet
us-gaap:DebtInstrument
us-gaap:DebtInstrument, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:LongtermDebtType
us-gaap:DebtLongtermAndShorttermCombinedAmount

us-gaap:DecreaseInUnrecognizedTaxBenefitsIsReasonablyPossible

us-gaap:DeferredCompensationLiabilityClassifiedNoncurrent

us-gaap:DeferredFinanceCostsNet
us-gaap:CreditFacility, us-gaap:LongtermDebtType

us-gaap:DeferredIncomeTaxAssetsNet

us-gaap:DeferredIncomeTaxLiabilities

us-gaap:DeferredTaxAssetsCapitalLossCarryforwards

us-gaap:DeferredTaxAssetsDeferredIncome

us-gaap:DeferredTaxAssetsGross

us-gaap:DeferredTaxAssetsOperatingLossCarryforwards

us-gaap:DeferredTaxAssetsOther

us-gaap:DeferredTaxAssetsTaxCreditCarryforwards

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits

us-gaap:DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities

us-gaap:DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts

us-gaap:DeferredTaxLiabilitiesOther

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment

us-gaap:DeferredTaxLiabilitiesUndistributedForeignEarnings
us-gaap:Range, us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DerivativeBasisSpreadOnVariableRate
us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation
us-gaap:DerivativeLiabilities
us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship
us-gaap:DerivativeLiabilitiesCurrent
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship
us-gaap:DerivativeLiabilitiesNoncurrent
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation

us-gaap:DerivativeNotionalAmount
us-gaap:DerivativeInstrumentRisk
us-gaap:StatementBusinessSegments
us-gaap:DisposalGroupIncludingDiscontinuedOperationConsideration

us-gaap:EmployeeRelatedLiabilitiesCurrent
us-gaap:AwardType
us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue

us-gaap:FinanceLeaseLiability

us-gaap:FinanceLeaseLiabilityCurrent

us-gaap:FinanceLeaseLiabilityNoncurrent

us-gaap:FinanceLeaseLiabilityPaymentsDue

us-gaap:FinanceLeaseLiabilityPaymentsDueNextTwelveMonths

us-gaap:FinanceLeaseLiabilityPaymentsDueYearFive

us-gaap:FinanceLeaseLiabilityPaymentsDueYearFour

us-gaap:FinanceLeaseLiabilityPaymentsDueYearThree

us-gaap:FinanceLeaseLiabilityPaymentsDueYearTwo

us-gaap:FinanceLeaseLiabilityUndiscountedExcessAmount

us-gaap:FinanceLeaseRightOfUseAsset

us-gaap:FinanceLeaseWeightedAverageDiscountRatePercent

us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFive

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFour

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearThree

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo

us-gaap:FiniteLivedIntangibleAssetsGross
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:StatementBusinessSegments
us-gaap:GoodwillImpairedAccumulatedImpairmentLoss

us-gaap:InterestPayableCurrent

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:LiabilitiesFairValueDisclosure
us-gaap:FairValueByMeasurementFrequency
us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:LineOfCredit
us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType
us-gaap:CreditFacility, us-gaap:LongtermDebtType
us-gaap:CreditFacility, us-gaap:LongtermDebtType
us-gaap:LineOfCreditFacilityCapacityAvailableForTradePurchases
us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:LineOfCreditFacilityInterestRateAtPeriodEnd
us-gaap:ConsolidatedEntities, us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity
us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrument, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:LongtermDebtType
us-gaap:LongTermDebtFairValue

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo

us-gaap:OperatingLeaseWeightedAverageDiscountRatePercent
us-gaap:IncomeTaxAuthority
us-gaap:OperatingLossCarryforwards

us-gaap:OtherLongTermInvestments
us-gaap:PropertyPlantAndEquipmentByType
us-gaap:PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization
us-gaap:PropertyPlantAndEquipmentByType
us-gaap:PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization

us-gaap:PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization
us-gaap:PropertyPlantAndEquipmentByType
us-gaap:SubsequentEventType
us-gaap:PurchaseObligation

us-gaap:RestrictedCashCurrent

us-gaap:RestructuringReserveCurrent

us-gaap:RevenueRemainingPerformanceObligation
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice
us-gaap:StatementClassOfStock
us-gaap:SharePrice
us-gaap:AwardType
us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1
us-gaap:StatementClassOfStock
us-gaap:StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1
us-gaap:IncomeTaxAuthorityName, us-gaap:TaxCreditCarryforward
us-gaap:TaxCreditCarryforwardAmount
us-gaap:IncomeTaxAuthorityName, us-gaap:TaxCreditCarryforward
us-gaap:TaxCreditCarryforwardValuationAllowance
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:TradingSecurities
us-gaap:FairValueByMeasurementFrequency

us-gaap:UnbilledReceivablesCurrent

us-gaap:UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued

us-gaap:ValuationAllowancesAndReservesBalance
us-gaap:RestructuringCostAndReserve, us-gaap:ValuationAllowancesAndReservesType
us-gaap:ValuationAllowancesAndReservesType

Plots across concepts


IncomeStatement
Net Income Loss
Expenses
Other Nonoperating Income Expense
Balance Sheet
Operating Lease Right Of Use Asset
Assets
Property Plant And Equipment Net
Current Assets
Prepaid Expense And Other Assets Current
NonCurrent Assets
Deferred Income Tax Assets Net
PropertyPlantAndEquipmentNet
Property Plant And Equipment Net
Liabilities
Operating Lease Liability
Current Liabilities
Taxes Payable Current
Noncurrent Liabilities
Deferred Income Tax Liabilities Net
Stockholders Equity
Retained Earnings Accumulated Deficit
CashFlow
Net Cash Provided By Used In Financing Activities
NetCashProvidedByUsedInOperatingActivities
Foreign Currency Transaction Gain Loss Realized
NetCashProvidedByUsedInInvestingActivities
Net Cash Provided By Used In Investing Activities
NetCashProvidedByUsedInFinancingActivities
Net Cash Provided By Used In Financing Activities
Shares
Common Stock Shares Issued
OperatingLeaseLiability
Operating Lease Liability Current
NonoperatingIncomeExpense
Nonoperating Income Expense
LesseeOperatingLeaseLiabilityPaymentsDue
Lessee Operating Lease Liability Payments Due Year Four
FiniteLivedIntangibleAssets
Finite Lived Intangible Assets Accumulated Amortization

Tables

  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
us-gaap:CommonStockValue ████████████████▁▁▁▁▁▁▁▁▁▂▂1.0351.0421.0391.041.0421.0421.0391.0381.0351.0381.0341.0321.0291.0381.0441.0420.5420.5410.5380.5360.5460.540.5390.5650.5630.6120.612NANANA1.051NANANA
us-gaap:CommonStockSharesIssued ▄▇▆▆▇▇▅▅▄▅▃▃▁▅█103.473104.226103.935103.994104.236104.161103.866103.793103.46103.753103.372103.223093102.871399103.803581104.435501NA54.17937454.08908753.76278653.57995854.56930554.00317953.87148456.48338156.25316561.25367361.23385NANANA105.137137NANANA
us-gaap:CommonStockSharesOutstanding ████████████████▁▁▁▁▁▁▁▁▁▂▂103.473104.226103.935103.994104.236104.161103.866103.793103.46103.753103.372103.223093102.871399103.803581104.435501104.21947154.17937454.08908753.76278653.57995854.56930554.00317953.87148456.48338156.25316561.25367361.23385NANANA103.794889NANANA
us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding ▁█105.019105.457NA105.588105.219105.642NA105.021104.818103.365NA103.012104.005104.449NA87.15255.30755.123NA55.56756.07855.862NA58.76460.46463.103NA52.51452.18551.897NANANANA
us-gaap:WeightedAverageNumberOfSharesOutstandingBasic ▁█103.937104.274NA104.277104.198104.265NA103.594103.699103.365NA103.012102.899104.449NA87.15254.12354.015NA54.18654.29853.955NA56.32558.23161.244NA51.90551.89851.897NANANANA
us-gaap:EarningsPerShareBasic ▇▇█▇▆▆█▇▆▅▇▅▆▅▅▁▆▇█▇▇▆▇▇▇▇▃▆▆▆▅▆▅▅0.40.370.88000000000000010.610.040.320.880.570.11-0.290.44-0.10.13-0.24-0.14-1.70.060.390.70.50.560.320.550.670.40.41-0.920.240.29-0.03-0.25-0.02-0.21-0.32
us-gaap:EarningsPerShareDiluted ▇▇█▇▆▇█▇▆▅▇▅▆▅▅▁▆▇▇▇▇▆▇▇▇▇▃▆▆▆▅▆▅▅0.40.370.87000000000000010.60.040.320.860.560.11-0.290.44-0.10.13-0.24-0.14-1.70.060.380.680.490.540.310.530.640.390.4-0.920.240.29-0.03-0.25-0.02-0.21-0.32
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
 COGS Ratio us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,synh:ClinicalSolutionsSegment█▆▄▃▁▅▅▄▄▃▃▃▂▂991.142937.954855.568829.163747.179874.826899.289867.427849.922804.958821.247819.203783.913786.839NANANANANANANANANANANANANANANANANANANANA
 COGS Ratio us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,synh:CommercialSolutionsSegment▄▂▃▁▁▄▇▆▇▇█▅▄▁291.469270.791284.451269.841266.22288.529313.665309.601316.905314.048324.225295.715288.617270.357NANANANANANANANANANANANANANANANANANANANA
 Operating Margin us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,synh:ClinicalSolutionsSegment█▆▄▃▁▅▅▄▄▃▃▃▂▂991.142937.954855.568829.163747.179874.826899.289867.427849.922804.958821.247819.203783.913786.839NANANA249.497NANANANANANANANANANANANANANANANA
 Operating Margin us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,synh:CommercialSolutionsSegment▄▂▃▁▁▄▇▆▇▇█▅▄▁291.469270.791284.451269.841266.22288.529313.665309.601316.905314.048324.225295.715288.617270.357NANANA2.581NANANANANANANANANANANANANANANANA
 SG&A Ratio us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,synh:ClinicalSolutionsSegment█▆▄▃▁▅▅▄▄▃▃▃▂▂991.142937.954855.568829.163747.179874.826899.289867.427849.922804.958821.247819.203783.913786.839NANANA249.497NANANANANANANANANANANANANANANANA
 SG&A Ratio us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,synh:CommercialSolutionsSegment▄▂▃▁▁▄▇▆▇▇█▅▄▁291.469270.791284.451269.841266.22288.529313.665309.601316.905314.048324.225295.715288.617270.357NANANA2.581NANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
 TTM Greenblatt ROC _ _▇▆██▅▆▇▇▆▅▇▆▅▄▅▁▄▅▆▆▆▅▆▆▅▅▅▅▄▅▅83.68461.015110.45198.75434.97148.96783.36169.44358.13426.81679.46839.81730.72210.17515.02-88.88810.2534.75243.839.39639.65532.50839.69344.34135.93932.38718.45322.7397.87214.5811.281NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
 us-gaap:AllocatedShareBasedCompensationExpense us-gaap:ConsolidationItems,us-gaap:IncomeStatementLocation us-gaap:CorporateNonSegment,synh:CostofServices▇█▇▇▇▇▆▆▇▇▅▅▅▄▁▅▄▃8.1279.0957.3597.78.1068.1826.6186.9197.3128.1624.795.2165.5723.752-0.5185.3882.9542.713NANANANANANANANANANANANANANANANA
 us-gaap:AllocatedShareBasedCompensationExpense us-gaap:ConsolidationItems,us-gaap:IncomeStatementLocation us-gaap:CorporateNonSegment,us-gaap:SellingGeneralAndAdministrativeExpenses██▃▇█▇▇▅▆▅▃▄▂▃▅▁▂▂8.3128.2583.8667.3938.0697.8167.7115.8846.4826.1053.4884.5752.8034.0365.4952.1653.2753.106NANANANANANANANANANANANANANANANA
us-gaap:ComprehensiveIncomeNetOfTax ▆▅█▇▅▄█▅▄▄▅▄▃▅▄▁▅▅▅▅▅▅▅▅▅▅▃▅▅▄55.43840.351141.406102.4675.65-25.944146.49224.573-9.589-13.61611.21-9.065-57.3269.805-11.892-143.48710.59226.18331.8929.08128.21122.74127.58736.93421.14516.038-55.113.62814.806-3.153NANANANA
us-gaap:CostOfGoodsAndServicesSold █▆▃▂▁▅▆▅▅▄▄▃▃▂992.581945.25848.008820.228805.892924.014927.9913.674917.529886.802873.808872.214847.465840.823NANA295.058284.675298.529291.875300.34316.148304.945251.181247.926222.851247.887220.418212.984202.841NANANANA
us-gaap:CostOfRevenue █▆▃▂▁▅▆▅▅▄▄▃▃▂992.581945.25848.008820.228805.892924.014927.9913.674917.529886.802873.808872.214847.465840.823NANA295.058284.675298.529291.875300.34316.148304.945251.181247.926222.851247.887220.418212.984202.841NANANANA
us-gaap:CostsAndExpenses ██▇▇▆▇▇▇▇▇▇▇▇▇▇▆▂▂▂▂▂▂▂▁▁▁▁▁▁▁1198.9271147.731029.5681000.25978.4281114.3881129.5931107.5851108.6931092.191066.0041075.1011041.8081047.0211061.663911.216380.885347.166362.271352.395359.992380.579363.192305.804301.353276.53309.202275.885277.871252.197NANANANA
us-gaap:GainsLossesOnExtinguishmentOfDebt ▂▂▂▂▃▃█▃▃▁▂▂▂▃▂▃▃▃▃▂▃-2.199-0.603-1.235-0.3460.00.014.80.00.0-4.355-0.3-1.789-1.877-0.248-0.5-0.1020.00.00.0-0.4390.0NA0.00.0-9.795NA-46.750.00.0NANANANANA
 us-gaap:GainsLossesOnExtinguishmentOfDebt us-gaap:LongtermDebtType us-gaap:SecuredDebt-2.2NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest ▇▇█▇▅▆▆▇▆▄▇▅▆▄▄▁▅▆▇▆▆▆▆▆▆▆▄▆▅▅51.03947.01186.86567.377.64841.77517.74569.97533.577-19.58859.5861.58929.607-33.524-18.672-121.8740.36228.30742.93733.40933.35124.42136.49440.30123.63130.548-37.94514.972-5.2880.057NANANANA
us-gaap:IncomeTaxExpenseBenefit ▇▇▆▆▆▇▁▇█▇▇▇▇▆▆█▆▇▇▇▆▇▇▆▆▇▇▆▅▆9.1348.287-5.0213.9543.7378.201-73.30511.05522.28510.413.87412.016.047-9.0-3.62526.124-3.0277.125.4466.0782.9487.0165.8382.4870.315.29211.8352.417-20.5951.609NANANANA
us-gaap:InterestExpense ▅▆▅▅▅▆▇██████▇▇▆▁▁▁▁▁▁▁▁▁▂▃▃▃▄22.61923.32823.01920.44221.68426.45828.3232.60734.26334.6332.97433.09732.89431.73629.90727.4323.2863.12.6993.2263.0873.0042.9533.0654.2335.38911.18312.92912.84116.083NANANANA
us-gaap:NetIncomeLoss ▇▆█▇▅▆█▇▆▄▇▅▆▅▅▁▅▆▆▆▆▆▆▆▆▆▄▆▆▅▅▅▅▅41.90538.72491.88663.4163.91133.57491.0558.9211.292-30.00445.67-10.39413.56-24.552-15.047-147.9983.38921.18737.49127.33130.40317.40530.65637.81423.32125.256-49.7812.55515.307-1.552-12.979-1.17-10.634-16.746
us-gaap:NonoperatingIncomeExpense ▄▆▅▄▅█▁▇▅▃▅▄▇▃▄▄▆▇▇▇▇▇▇▇▆▇▂▇▆▆-32.645-14.004-23.586-31.384-27.3237.192-65.6160.532-24.557-46.404-19.882-38.228-1.115-43.699-33.692-32.986-9.888-6.445-0.863-5.987-6.304-8.087-3.199-4.04-12.308-1.839-56.398-7.767-13.16-14.523NANANANA
us-gaap:OperatingIncomeLoss ▇▆██▅▆▇▇▆▅▇▆▅▄▅▁▄▅▆▆▆▅▆▆▅▅▅▅▄▅▅▅▄▄83.68461.015110.45198.75434.97148.96783.36169.44358.13426.81679.46839.81730.72210.17515.02-88.88810.2534.75243.839.39639.65532.50839.69344.34135.93932.38718.45322.7397.87214.5811.28115.0214.7860.37
 us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax us-gaap:StatementEquityComponents us-gaap:AccumulatedOtherComprehensiveIncome▁█4.7085.937NA5.219-1.131-10.735.5080.074-8.962-4.216NANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherNonoperatingIncomeExpense ▅▆▅▅▅▄▁█▆▅▆▅█▄▅▅▅▅▆▅▅▅▅▅▆▆▆▆▅▅-7.8279.8560.403-10.596-5.761-18.93-53.52730.7137.573-8.92113.143-4.34632.001-12.554-3.682-5.953-6.754-3.4571.759-2.384-3.26-5.117-0.281-1.0031.6753.4661.5125.136-0.3371.378NANANANA
us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax ██▇▇▆▇█▇▇▇▇▇▇▇▅▅▂▂▂▂▃▃▂▂▂▂▁▂▂▂▁▁▁▁1282.6111208.7451140.0191099.0041013.3991163.3551212.9541177.0281166.8271119.0061145.4721114.9181072.531057.196750.471822.328391.135252.078262.979391.791399.647413.087241.356350.145337.292308.917213.725298.624285.743266.777174.365169.108159.202149.743
us-gaap:SellingGeneralAndAdministrativeExpense ██▆▆▆▆▆▆▆▆▆▅▅▅▆▅▂▂▂▂▂▂▂▂▁▁▂▁▁▁144.669137.314108.442111.096104.976117.97112.421109.864110.879113.117109.88596.943100.21899.259106.388.85542.53144.93444.56841.74342.59643.47943.25540.42937.12535.840.81138.18533.96232.185NANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
us-gaap:Assets ███▇▇█▇▇▇▇▇▇▇▇▇▇▁▁▁▁▁▁▁▁▁▁▁8019.6747954.6498063.3067384.7317407.1317590.2927453.7957377.3137396.9817387.537254.9097209.6937173.27241.9047285.8677296.9541336.2591291.5981288.5071244.1541252.1041228.3421211.2191303.0411215.7441276.5031245.087NANANA1233.111NANANA
us-gaap:Liabilities ███▇▇█▇▇██▇▇▇▇▇▇▁▁▁▁▁▁▁▁▁▁▁4781.064717.7724821.1944288.2534407.4474612.374424.1414509.7974573.0824549.164398.7654376.6654350.5284334.6454263.2884270.645982.821956.152987.034982.292963.467976.285993.785985.188935.376867.549852.878NANANA956.904NANANA
us-gaap:LiabilitiesAndStockholdersEquity ███▇▇█▇▇▇▇▇▇▇▇▇▇▁▁▁▁▁▁▁▁▁▁▁8019.6747954.6498063.3067384.7317407.1317590.2927453.7957377.3137396.9817387.537254.9097209.6937173.27241.9047285.8677296.9541336.2591291.5981288.5071244.1541252.1041228.3421211.2191303.0411215.7441276.5031245.087NANANA1233.111NANANA
us-gaap:StockholdersEquity ████▇▇█▇▇▇▇▇▇▇▇█▁▁▁▁▁▁▁▁▁▁▁3238.6143236.8773242.1123096.4782999.6842977.9223029.6542867.5162823.8992838.372856.1442833.0282822.6722907.2593022.5793026.309353.438335.446301.473261.862288.637252.057217.434317.853280.368408.954392.209NANANA276.207NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
us-gaap:AssetsCurrent █▇█▇▇█▇▇▆▆▇▆▆▆▆▆▂▂▂▁▁▁▁▂▁▁▁1748.2961674.3781738.0121595.7131597.3991774.5371562.1641492.5121466.751407.761491.9621356.4221417.0731388.5121422.1791362.802582.727539.146522.629487.041484.429450.078422.046521.302426.687477.322426.899NANANA376.182NANANA
 us-gaap:CashAndCashEquivalentsAtCarryingValue us-gaap:ConcentrationRiskByType,us-gaap:GeographicDistribution us-gaap:CustomerConcentrationRisk,us-gaap:GeographicDistributionForeign145.0NA50.7NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents ▆▆▆▅██▃▂▁▁▃▂▃▄▇▇▃▃▁261.135264.689272.173248.896343.03335.96163.689129.204107.256107.921155.932134.604173.719188.955321.976305.528170.29165.04103.078NANANA85.463NANANANANANANANANANANA
us-gaap:PrepaidExpenseAndOtherAssetsCurrent █▇█▅▅▆▆▄▄▅▅▅▅▆▅▆▂▁▂▂▂▁▂▂▂▁▂117.24110.521121.05882.31580.34897.92994.83468.21971.98578.17979.29980.41882.96494.29184.21596.89437.90427.27234.20236.00835.81933.76838.57137.42334.46630.96535.393NANANA35.428NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
us-gaap:PropertyPlantAndEquipmentGross NANA467.169NANANA409.401NANANA337.61NANANA277.758250.285NANA121.95NANANA92.032NANANA82.932NANANA93.148NANANA
 us-gaap:PropertyPlantAndEquipmentGross us-gaap:PropertyPlantAndEquipmentByType synh:AssetsNotYetPlacedInServiceNANA28.129NANANA20.262NANANA11.011NANANA29.215NANANA13.396NANANANANANANANANANANANANANANA
 us-gaap:PropertyPlantAndEquipmentGross us-gaap:PropertyPlantAndEquipmentByType us-gaap:BuildingAndBuildingImprovementsNANA5.211NANANA4.256NANANA4.348NANANA4.5524.485NANA4.004NANANA4.597NANANANANANANANANANANA
 us-gaap:PropertyPlantAndEquipmentGross us-gaap:PropertyPlantAndEquipmentByType us-gaap:ComputerEquipmentNANA108.23NANANA95.228NANANA82.28NANANA61.65956.009NANA26.311NANANA23.764NANANA20.588NANANA26.798NANANA
 us-gaap:PropertyPlantAndEquipmentGross us-gaap:PropertyPlantAndEquipmentByType us-gaap:FurnitureAndFixturesNANA37.287NANANA33.388NANANA24.006NANANA19.31720.24NANA10.894NANANA9.173NANANA8.301NANANA7.346NANANA
 us-gaap:PropertyPlantAndEquipmentGross us-gaap:PropertyPlantAndEquipmentByType us-gaap:LeaseholdImprovementsNANA94.596NANANA86.327NANANA69.632NANANA58.97553.297NANA14.814NANANA13.92NANANA12.424NANANA10.016NANANA
 us-gaap:PropertyPlantAndEquipmentGross us-gaap:PropertyPlantAndEquipmentByType us-gaap:SoftwareAndSoftwareDevelopmentCostsNANA129.731NANANA99.5NANANA91.04NANANA65.10264.575NANA52.531NANANA33.087NANANA30.807NANANA38.469NANANA
 us-gaap:PropertyPlantAndEquipmentGross us-gaap:PropertyPlantAndEquipmentByType us-gaap:VehiclesNANA63.985NANANA70.44NANANA55.293NANANA38.93837.347NANA0.0NANANANANANANANANANANANANANANA
us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment NANA250.969NANANA205.475NANANA154.124NANANA97.34677.373NANA63.644NANANA47.219NANANA39.207NANANA52.201NANANA
us-gaap:AmortizationOfIntangibleAssets ▅▅▅▅▅▅▅▅▅▅▆▆▆▆█▆▁▁▁▁▁▁▁▁▁▁▁▁▁▁39.55339.49136.42138.14738.71738.88241.5141.29341.50141.62951.19450.39549.94549.99365.2251.3839.4629.4649.4639.4649.4639.4619.4619.4629.4739.4789.5879.5976.2387.502NANANANA
us-gaap:PropertyPlantAndEquipmentNet █▇█▇▇▇█▇▇▆▇▆▆▆▇▆▂▂▂▁▁▁▁▁▁▁▁203.988202.618216.2196.258197.074195.62203.926201.122187.747175.99183.486175.128163.5173.051180.412172.91258.55857.48558.30645.9646.3545.52544.81339.73440.46941.81343.725NANANA40.947NANANA
us-gaap:Goodwill ███▇▇▇▇▇▇▇▇▇▇▇▇▇▁▁▁▁▁▁▁▁▁▁▁4789.7844780.1794776.1784343.3544323.2294323.4364350.384322.1834336.3554344.7444333.1594352.8254275.4854306.2444292.5714265.175553.158553.071552.502553.026552.815553.218553.008552.838553.584553.597556.863NANANA563.365NANANA
us-gaap:IntangibleAssetsNetExcludingGoodwill ▅▅▆▅▅▅▆▆▆▆▇▇▇▇▇█▁▁▁▁▁▁▁▁▁▁▂831.072896.386933.525882.485913.375925.389973.0811004.5761051.0651096.6191133.6121189.6651182.5711241.7091286.051394.72895.61105.074114.486124.004133.434142.93152.34161.755171.323180.801190.359NANANA231.051NANANA
us-gaap:FiniteLivedIntangibleAssetsNet NANA933.525NANANA973.081NANANA1133.6121189.665NANA1286.051394.728NA1286.0579.486NANANA117.34NANANA155.359NANANA196.051NANANA
 us-gaap:FiniteLivedIntangibleAssetsNet us-gaap:FiniteLivedIntangibleAssetsByMajorClass us-gaap:CustomerRelationshipsNANA833.06NANANA944.236NANANA1080.851120.919NANA1174.021142.576NANA79.486NANANA117.34NANANA155.338NANANA194.553NANANA
 us-gaap:FiniteLivedIntangibleAssetsNet us-gaap:FiniteLivedIntangibleAssetsByMajorClass us-gaap:IntellectualPropertyNANA28.36NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:FiniteLivedIntangibleAssetsNet us-gaap:FiniteLivedIntangibleAssetsByMajorClass us-gaap:OrderOrProductionBacklogNANA41.447NANANA15.293NANANA35.5950.518NANA95.347225.674NANA0.0NANANA0.0NANANA0.0NANANA1.35NANANA
 us-gaap:FiniteLivedIntangibleAssetsNet us-gaap:FiniteLivedIntangibleAssetsByMajorClass us-gaap:TrademarksAndTradeNamesNANA30.658NANANA13.552NANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:IntangibleAssetsNetIncludingGoodwill us-gaap:FairValueByMeasurementFrequency us-gaap:FairValueMeasurementsNonrecurring▇██▁▁▁▂▂▃▄▄▆▄▆▆▇5650.05680.05710.05230.05240.05250.05320.05330.05390.05440.05470.05540.05460.05550.05578.65659.9NANA667.0NANANA705.3NANANANANANANANANANANA
us-gaap:DeferredTaxAssetsLiabilitiesNet NANA14.842NANANA25.911NANANANANANANANANANANANANANANANANANANA1.155NANANA-11.743NANANA
us-gaap:OperatingLeaseRightOfUseAsset ▇▇█▇▇▇▇▇██▁222.034215.048223.285213.056211.295218.437218.531220.346227.715239.3910.0NANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherAssetsNoncurrent █▇▆▆▆▅▅▆▅▅▅▅▅▅▄▄▁▁▂▁▁▂▂▁▁▁▁186.886151.076141.047135.609130.447118.634108.701131.072118.238113.873103.373102.951101.758104.67984.49680.019.65518.68625.85823.61123.96724.50826.93911.50211.4611.61511.576NANANA17.786NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
us-gaap:AccountsPayableCurrent ▆▇▇▆▅▇█▅█▆▆▅▅▄▄▄▂▁▂▁▂▃▁▁▁▁▁107.772113.881113.684104.93692.488112.312136.68682.838128.81294.27898.62482.20485.8169.558.57566.03126.73118.85123.69322.20627.09240.3722.49714.34814.75614.0116.548NANANA9.594NANANA
us-gaap:AccruedLiabilitiesCurrent █▇█▇▇▆▇█▇▇▇▇▆▇▆▆▂▁▂▂▂▂▁▁▁▁▁625.623587.757611.042583.015532.356504.351568.911587.895569.446535.521563.527527.225502.646518.383500.303445.958158.169133.663153.559146.146147.545144.957111.262110.505100.27197.026111.655NANANA94.221NANANA
us-gaap:ContractWithCustomerLiabilityCurrent █▇█▅▄▅▅▅▅▅▇▅▆▃▁802.256773.025793.068710.17657.98689.672696.907703.916710.905713.313777.141709.027719.932643.338559.27NANANANANANANANANANANANANANANANANANANA
us-gaap:LiabilitiesCurrent █▇█▇▇▇▇▇█▇▇▇▆▆▅▅▂▁▁▂▂▂▂▁▁▁▁1596.3481532.2851577.3311511.2531426.7211441.0091516.4611451.7341654.5021383.7121503.1981397.1091361.0891278.361159.5621073.61507.223458.247466.727482.721474.467472.884474.592462.185412.231398.05379.796NANANA318.008NANANA
us-gaap:LongTermDebtCurrent NANANA56.87587.18777.558.12528.75199.5750.050.162.0537.531.2525.030.7523.7517.81311.87530.93815.6255.78129.8040.00.04.254.25NANANA4.713NANANA
us-gaap:OperatingLeaseLiabilityCurrent █▄▆▃▅▄▁43.63640.75942.08239.56840.98240.1338.055NA29.76NA0.0NANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherAccruedLiabilitiesCurrent NANA45.742NANANA45.27NANANA45.272NANANA53.58357.79NANA29.184NANANA16.88917.9321.26819.49616.073NANANA13.474NANANA
us-gaap:TaxesPayableCurrent NANA28.89NANANA17.295NANANA30.761NANANA16.8128.354NANA1.072NANANA4.20213.0410.0489.91810.784NANANA3.973NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
us-gaap:LongTermDebt ▇▇█▁▅█▃▄▅▆▆2863.622862.5742902.0542522.2332740.552909.2222608.522708.8612734.4172785.6582787.119NANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LongTermDebtNoncurrent ███▇▇█▇▇▇▇▇▇████▁▁▁▁▁▁▁▁▁▁▁2863.622862.5742902.0542465.3582653.3632831.7222550.3952680.1112534.8422785.6582737.0192775.6312835.3212908.3662945.9342984.785449.258470.053485.849466.641456.804466.45472.035475.0475.0414.45415.277NANANA587.202NANANA
us-gaap:DeferredIncomeTaxLiabilitiesNet ▃▃▃▂▂▂▂▅▅▄▄█▅▄▆▇▁13.73917.04320.2167.9319.518.98911.10133.533.22326.82325.1258.61232.55722.26537.80751.1080.316NA8.295NANANANANANANANANANANANANANANA
us-gaap:OtherLiabilitiesNoncurrent ▄▄▄▄▅▅▅▅▅▅▆▇▆▆▆█▁▁▁▂▂▁▁▁▁▁▁64.13164.4468.31165.60282.29683.19890.92785.57793.42188.918106.669123.745108.32110.04799.609139.03826.02425.94926.16328.86828.44722.00819.09220.17720.90926.52327.426NANANA22.189NANANA
us-gaap:OperatingLeaseLiabilityNoncurrent ▆▄█▂▁▅▆217.341213.662221.76209.809207.588215.375218.343NA228.704NA0.0NANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo NANA51.849NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree NANA45.092NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour NANA37.326NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive NANA29.893NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive NANA99.031NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
us-gaap:StockholdersEquity ████▇▇█▇▇▇▇▇▇▇▇█▁▁▁▁▁▁▁▁▁▁▁3238.6143236.8773242.1123096.4782999.6842977.9223029.6542867.5162823.8992838.372856.1442833.0282822.6722907.2593022.5793026.309353.438335.446301.473261.862288.637252.057217.434317.853280.368408.954392.209NANANA276.207NANANA
us-gaap:CommonStockValue ████████████████▁▁▁▁▁▁▁▁▁▂▂1.0351.0421.0391.041.0421.0421.0391.0381.0351.0381.0341.0321.0291.0381.0441.0420.5420.5410.5380.5360.5460.540.5390.5650.5630.6120.612NANANA1.051NANANA
us-gaap:AdditionalPaidInCapital ████████████████▁▁▁▁▁▁▁▁▁▁▁3430.3753440.843461.7473454.3813446.8523430.743441.4713425.8263404.3893402.9533402.6383390.7343371.3163394.5863414.3893404.506590.371582.972573.176565.457572.6564.237559.91584.002583.453635.653634.946NANANA480.579NANANA
us-gaap:RetainedEarningsAccumulatedDeficit ███▆▅▅▄▃▁▁▂▁▁▁▄▄▇▇▇▆▆▆▅▇▆▇▇-167.155-165.831-179.873-268.622-318.838-322.749-341.263-432.313-488.837-493.814-459.333-505.003-494.609-504.187-370.469-353.699-207.424-210.813-229.991-267.482-246.11-276.513-301.472-228.24-266.054-191.893-217.149NANANA-188.831NANANA
us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax ▆▅▅▃▁▁▄▁▃▄▃▅▅█▆▆▆▅▅▆▅▆▅▅▅▆▆-25.641-39.174-40.801-90.321-129.372-131.111-71.593-127.035-92.688-71.807-88.195-53.735-55.06415.822-22.385-25.54-30.051-37.254-42.25-36.649-38.399-36.207-41.543-38.474-37.594-35.418-26.2NANANA-9.841NANANA
 us-gaap:StockIssuedDuringPeriodValueNewIssues us-gaap:StatementEquityComponents us-gaap:AdditionalPaidInCapital▆▁▅▇▅▄▅█▆2.874-18.4431.1249.231-0.063-6.9951.31613.2824.377NANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:StockIssuedDuringPeriodValueNewIssues us-gaap:StatementEquityComponents us-gaap:CommonStock▃█▂▃▁█▂▄▃0.0020.0090.0010.0030.00.0090.0010.0040.002NANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue us-gaap:StatementEquityComponents us-gaap:AdditionalPaidInCapital▇█▃▆▇▇▆▅▅▆▁▂▁▁16.43917.35311.22515.09316.17515.99814.32912.80313.79414.2678.2789.7918.3757.879NANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
us-gaap:NetCashProvidedByUsedInOperatingActivities ▅▆▆▇█▁▇▅▅▂▆▆▆▁▅▃▃▅▃▄▄▂▄▄▄▄▃▃▄▃88.707127.088114.326156.002193.772-38.607160.54874.41996.82-13.306112.448125.826112.159-46.98588.51211.32222.72675.69814.20850.74845.022-0.64663.61845.84751.64443.63114.11936.93249.18631.21NANANANA
us-gaap:NetCashProvidedByUsedInInvestingActivities ██▆████████████▁██████████████-11.499-19.781-458.732-8.072-18.66-18.62-21.789-28.806-19.621-11.445-11.632-101.267-11.3-21.286-15.928-1691.005-5.403-10.571-14.527-5.336-6.716-4.774-9.546-3.896-2.799-4.87-7.812-4.8-8.315-6.926NANANANA
us-gaap:NetCashProvidedByUsedInFinancingActivities ▂▁▃▁▁▃▂▂▂▂▂▂▁▂▂█▂▂▂▂▂▂▁▂▁▂▂▂▂▂-79.457-111.366366.441-244.414-173.68229.918-91.584-23.97-73.577-26.338-72.679-66.983-109.817-69.877-55.881810.176-13.908-6.023.462-35.8665.54-26.452-102.015-1.991-106.131-1.262-59.485-0.89-0.932-6.391NANANANA
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect ▄▄▅▂▄█▅▅▄▃▅▃▄▁▄▇▄▅-3.554-7.48423.277-94.1347.07172.27134.48521.948-0.665-48.01121.328-39.115-15.236-133.02116.448135.2385.2561.962NANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
us-gaap:AmortizationOfFinancingCosts NANA0.0010.0040.0710.0-0.1591.5821.7322.2410.00.4091.3170.0NANANANANANANANANANANANANANANANANANANANA
us-gaap:DeferredIncomeTaxExpenseBenefit ▅▆▄▇▆▇▁▆▇▆▆▇▆▅▆█▅▆▄▆▆▆▆▆▆▆▇▆▄▆-8.371-4.653-25.14512.5560.5918.159-53.164.2987.2491.5440.9616.9613.053-10.7351.69821.814-9.1680.087-17.0340.105-4.063-1.2684.0220.395-1.2220.9397.3960.209-22.9550.513NANANANA
us-gaap:DepreciationDepletionAndAmortization ▅▅▅▅▅▅▆▆▆▆▇▆▆▆█▆▁▁▁57.71157.93854.77655.44856.02156.10760.37960.13760.74961.270.12868.03467.50268.02183.34865.43215.52815.62815.559NANANANANANANANANANANANANANANA
us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet █▅██▃▇▁▇▂▆▄▁▃▃▄▂▆▄▃▄▅▃▅▅▆▄▄▄▅▄21.2365.03924.20122.564-6.52215.202-19.40216.954-10.38613.8210.798-17.852-9.278-7.5210.041-11.40610.652-2.673-9.849-1.1162.741-5.5963.8365.038.672-2.683-3.3151.7233.115-2.743NANANANA
us-gaap:NetCashProvidedByUsedInOperatingActivities ▅▆▆▇█▁▇▅▅▂▆▆▆▁▅▃▃▅▃▄▄▂▄▄▄▄▃▃▄▃88.707127.088114.326156.002193.772-38.607160.54874.41996.82-13.306112.448125.826112.159-46.98588.51211.32222.72675.69814.20850.74845.022-0.64663.61845.84751.64443.63114.11936.93249.18631.21NANANANA
us-gaap:NetIncomeLoss ▇▆█▇▅▆█▇▆▄▇▅▆▅▅▁▅▆▆▆▆▆▆▆▆▆▄▆▆▅▅▅▅▅41.90538.72491.88663.4163.91133.57491.0558.9211.292-30.00445.67-10.39413.56-24.552-15.047-147.9983.38921.18737.49127.33130.40317.40530.65637.81423.32125.256-49.7812.55515.307-1.552-12.979-1.17-10.634-16.746
us-gaap:ShareBasedCompensation ▄▄▃▄▄▄▄▃▃▄▂▃▂▂▃█▂▂▂▂▁▁▁▁▁▁▁▁▁▁16.43917.35311.22515.09316.17515.99814.32912.80313.79414.2678.2789.7918.3757.8798.76838.886.2295.8194.6163.5173.0712.8161.7861.6680.9130.7071.0650.8810.8930.531NANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
us-gaap:NetCashProvidedByUsedInInvestingActivities ██▆████████████▁██████████████-11.499-19.781-458.732-8.072-18.66-18.62-21.789-28.806-19.621-11.445-11.632-101.267-11.3-21.286-15.928-1691.005-5.403-10.571-14.527-5.336-6.716-4.774-9.546-3.896-2.799-4.87-7.812-4.8-8.315-6.926NANANANA
us-gaap:PaymentsToAcquirePropertyPlantAndEquipment ▄▄▄▃▆▄▅█▆▄▄▄▄█▆▄▂▄▅▂▂▂▃▁▁▂▃▂▃▂11.16411.17311.5178.41518.20811.8713.32822.57916.62111.44511.63210.37711.321.28615.74312.1795.40310.57114.5275.3366.7164.7749.5463.8962.7994.877.8124.88.3154.624NANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
us-gaap:NetCashProvidedByUsedInFinancingActivities ▂▁▃▁▁▃▂▂▂▂▂▂▁▂▂█▂▂▂▂▂▂▁▂▁▂▂▂▂▂-79.457-111.366366.441-244.414-173.68229.918-91.584-23.97-73.577-26.338-72.679-66.983-109.817-69.877-55.881810.176-13.908-6.023.462-35.8665.54-26.452-102.015-1.991-106.131-1.262-59.485-0.89-0.932-6.391NANANANA
us-gaap:RepaymentsOfLongTermDebt █▂▄▂▁▁▂▃▂▄▂▅▂▁▂█▁▁▁▁▁▁▁▁█▁▃▁▁▁496.421105.856213.54494.37519.3750.067.0114.840.0216.13636.25256.89666.2531.2550.0475.0970.00.00.00.00.00.00.00.0473.9381.063158.6420.00.05.453NANANANA
us-gaap:PaymentsForRepurchaseOfCommonStock █▅▂▄▁▄▁▂▃▄▁▁▅▅▁▁▁▁▁▇73.01644.5058.12230.00.032.0290.07.04523.05526.6160.00.037.49237.4930.00.00.00.00.064.5NANA135.00.0NANA0.00.019NANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument,us-gaap:LongtermDebtType synh:SeniorUnsecuredNotesDue2024,us-gaap:UnsecuredDebtNANA3.625e-06NANANA7.5e-08NANANA7.5e-08NANANA7.5e-08NANANANANANANANANANANANANANANANANANANA

Common Stock Value

us-gaap:CommonStockValue

us-gaap:CommonStockValue


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value1035000.01042000.01039000.01040000.01042000.01042000.01039000.01038000.01035000.01038000.01034000.01032000.01029000.01038000.01044000.01042000.0542000.0541000.0538000.0536000.0546000.0540000.0539000.0565000.0563000.0612000.0612000.01051000.0
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.1

Common Stock Shares Issued

us-gaap:CommonStockSharesIssued

us-gaap:CommonStockSharesIssued


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value1031041031031041041031031031031031031021031045454535354545356566161105
Percentage of CommonStockSharesIssued100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Common Stock Shares Outstanding

us-gaap:CommonStockSharesOutstanding

us-gaap:CommonStockSharesOutstanding


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value1031041031031041041031031031031031031021031041045454535354545356566161103
Percentage of CommonStockSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Diluted Shares Outstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding


Weighted
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-31
Value105105105105105105104103103104104875555555655586063525251
Percentage of WeightedAverageNumberOfDilutedSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Shares Outstanding Basic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic


Weighted
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-31
Value103104104104104103103103103102104875454545453565861515151
Percentage of WeightedAverageNumberOfSharesOutstandingBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Basic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareBasic


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value0.40.370.880.610.040.320.880.570.11-0.290.44-0.10.13-0.24-0.14-1.70.060.390.70.50.560.320.550.670.40.41-0.920.240.29-0.03-0.25-0.02-0.21-0.32
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Diluted

us-gaap:EarningsPerShareDiluted

us-gaap:EarningsPerShareDiluted


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value0.40.370.870.60.040.320.860.560.11-0.290.44-0.10.13-0.24-0.14-1.70.060.380.680.490.540.310.530.640.390.4-0.920.240.29-0.03-0.25-0.02-0.21-0.32
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Allocated Share Based Compensation Expense

us-gaap:AllocatedShareBasedCompensationExpense us-gaap:ConsolidationItems, us-gaap:IncomeStatementLocation

us-gaap:AllocatedShareBasedCompensationExpense

us-gaap:CorporateNonSegment, synh:CostofServices


Allocated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value8.1279.0957.3597.78.1068.1826.6186.9197.3128.1624.795.2165.5723.752-0.5185.3882.9542.713
Percentage of AllocatedShareBasedCompensationExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.60.80.60.70.80.70.50.60.60.70.40.50.50.4-0.10.70.81.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CorporateNonSegment synh:CostofServices0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CorporateNonSegment, us-gaap:SellingGeneralAndAdministrativeExpenses


Allocated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value8.3128.2583.8667.3938.0697.8167.7115.8846.4826.1053.4884.5752.8034.0365.4952.1653.2753.106
Percentage of AllocatedShareBasedCompensationExpense102.390.852.596.099.595.5116.585.088.674.872.887.750.3107.6-1060.840.2110.9114.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.60.70.30.70.80.70.60.50.60.50.30.40.30.40.70.30.81.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CorporateNonSegment us-gaap:SellingGeneralAndAdministrativeExpenses0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Comprehensive Income Net Of Tax

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:ComprehensiveIncomeNetOfTax


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value55401411025.65-25.94414624-9.589-13.61611-9.065-57.3269.805-11.892-143.48710263129282227362116-55.113.62814-3.153
Percentage of ComprehensiveIncomeNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax4.33.312.49.30.6-2.212.12.1-0.8-1.21.0-0.8-5.30.9-1.6-17.42.710.412.17.47.15.511.410.56.35.2-25.81.25.2-1.2

Cost Of Goods And Services Sold

us-gaap:CostOfGoodsAndServicesSold

us-gaap:CostOfGoodsAndServicesSold


Cost
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value992945848820805924927913917886873872847840295284298291300316304251247222247220212202
Percentage of CostOfGoodsAndServicesSold100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax77.478.274.474.679.579.476.577.678.679.276.378.279.079.575.4112.9113.574.575.276.5126.371.773.572.1116.073.874.576.0

us-gaap:CostOfGoodsAndServicesSold us-gaap:ConsolidationItems

us-gaap:OperatingSegments


Cost
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value984936840812797915921906910878869866841837
Percentage of CostOfGoodsAndServicesSold99.299.099.199.199.099.199.399.299.299.199.599.499.399.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax76.877.473.773.978.778.776.077.078.078.575.977.878.579.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CostOfGoodsAndServicesSold us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, synh:ClinicalSolutionsSegment


Cost
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value750716625600590677680655654625620633608615
Percentage of CostOfGoodsAndServicesSold75.675.873.873.273.273.373.371.871.370.671.072.671.973.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax58.559.254.954.758.258.256.155.756.155.954.256.856.858.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments synh:ClinicalSolutionsSegment75.876.30.072.479.077.40.075.677.077.70.077.377.778.2

us-gaap:OperatingSegments, synh:CommercialSolutionsSegment


Cost
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value233220215211207238241250255252248233232221
Percentage of CostOfGoodsAndServicesSold23.523.325.425.825.725.826.027.527.928.528.526.827.526.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax18.218.218.919.320.520.519.921.321.922.621.721.021.721.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments synh:CommercialSolutionsSegment80.281.30.078.577.982.70.081.080.780.50.079.080.782.0

Cost Of Revenue

us-gaap:CostOfRevenue

us-gaap:CostOfRevenue


Cost
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value992945848820805924927913917886873872847840295284298291300316304251247222247220212202
Percentage of CostOfRevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax77.478.274.474.679.579.476.577.678.679.276.378.279.079.575.4112.9113.574.575.276.5126.371.773.572.1116.073.874.576.0

Costs And Expenses

us-gaap:CostsAndExpenses

us-gaap:CostsAndExpenses


Costs
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value11981147102910009781114112911071108109210661075104110471061911380347362352359380363305301276309275277252
Percentage of CostsAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax93.595.090.391.096.595.893.194.195.097.693.196.497.199.0141.5110.897.4137.7137.889.990.192.1150.587.389.389.5144.792.497.294.5

Gains Losses On Extinguishment Of Debt

us-gaap:GainsLossesOnExtinguishmentOfDebt

us-gaap:GainsLossesOnExtinguishmentOfDebt


Gains
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312015-09-302015-06-302014-12-312014-09-302014-06-30
Value-2.199-0.603-1.235-0.3460.00.0140.00.0-4.355-0.3-1.789-1.877-0.248-0.5-0.1020.00.00.0-0.4390.00.00.0-9.795-46.750.00.0
Percentage of GainsLossesOnExtinguishmentOfDebt100.0100.0100.0100.00.00.0100.00.00.0100.0100.0100.0100.0100.0100.0100.00.00.00.0100.00.00.00.0100.0100.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.2-0.0-0.1-0.00.00.01.20.00.0-0.4-0.0-0.2-0.2-0.0-0.1-0.00.00.00.0-0.10.00.00.0-2.9-21.90.00.0

us-gaap:GainsLossesOnExtinguishmentOfDebt us-gaap:LongtermDebtType

us-gaap:SecuredDebt


Gains
Period End2021-06-30
Value-2.2
Percentage of GainsLossesOnExtinguishmentOfDebt100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:SecuredDebt0.0

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

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value514786677.64841176933-19.588591.58929-33.524-18.672-121.8740.362284233332436402330-37.94514-5.2880.057
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax4.03.97.66.10.83.61.55.92.9-1.85.20.12.8-3.2-2.5-14.80.111.216.38.58.35.915.111.57.09.9-17.85.0-1.90.0

Income Tax Expense Benefit

us-gaap:IncomeTaxExpenseBenefit

us-gaap:IncomeTaxExpenseBenefit


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value9.1348.287-5.0213.9543.7378.201-73.305112210131216-9.0-3.62526-3.0277.125.4466.0782.9487.0165.8382.4870.315.292112.417-20.5951.609
Percentage of IncomeTaxExpenseBenefit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.70.7-0.40.40.40.7-6.00.91.90.91.21.11.5-0.9-0.53.2-0.82.82.11.60.71.72.40.70.11.75.50.8-7.20.6

Interest Expense

us-gaap:InterestExpense

us-gaap:InterestExpense


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value222323202126283234343233323129273.2863.12.6993.2263.0873.0042.9533.0654.2335.38911121216
Percentage of InterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.81.92.01.92.12.32.32.82.93.12.93.03.13.04.03.30.81.21.00.80.80.71.20.91.31.75.24.34.56.0

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value413891633.91133915811-30.00445-10.39413-24.552-15.047-147.9983.389213727301730372325-49.781215-1.552-12.979-1.17-10.634-16.746
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.33.28.15.80.42.97.55.01.0-2.74.0-0.91.3-2.3-2.0-18.00.98.414.37.07.64.212.710.86.98.2-23.34.25.4-0.6-7.4-0.7-6.7-11.2

us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Net
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value4138633.911335811-30.00445-10.39413-24.552
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.33.25.80.42.95.01.0-2.74.0-0.91.3-2.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.0

Nonoperating Income Expense

us-gaap:NonoperatingIncomeExpense

us-gaap:NonoperatingIncomeExpense


Nonoperating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-32645000.0-14004000.0-23586000.0-31384000.0-27323000.07192000.0-65616000.0532000.0-24557000.0-46404000.0-19882000.0-38228000.0-1115000.0-43699000.0-33692000.0-32986000.0-9888000.0-6445000.0-863000.0-5987000.0-6304000.0-8087000.0-3199000.0-4040000.0-12308000.0-1839000.0-56398000.0-7767000.0-13160000.0-14523000.0
Percentage of NonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2.5-1.2-2.1-2.9-2.70.6-5.40.0-2.1-4.1-1.7-3.4-0.1-4.1-4.5-4.0-2.5-2.6-0.3-1.5-1.6-2.0-1.3-1.2-3.6-0.6-26.4-2.6-4.6-5.4

Operating Income Loss

us-gaap:OperatingIncomeLoss

us-gaap:OperatingIncomeLoss


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value8361110983448836958267939301015-88.8881034433939323944353218227.8721411154.7860.37
Percentage of OperatingIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax6.55.09.79.03.54.26.95.95.02.46.93.62.91.02.0-10.82.613.816.710.19.97.916.412.710.710.58.67.62.85.56.58.93.00.2

us-gaap:OperatingIncomeLoss us-gaap:ConsolidationItems

us-gaap:OperatingSegments


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value18816420319813214819918016614418416214013414611463637265
Percentage of OperatingIncomeLoss225.3268.9184.0201.4377.5303.4239.2259.5286.9539.3232.6406.9458.51323.4975.0-128.9622.0181.8166.0165.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax14.713.617.818.113.012.816.415.314.312.916.114.513.112.719.513.916.325.127.616.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OperatingIncomeLoss us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, synh:ClinicalSolutionsSegment


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value15113415616293123149142127109132122106105111886362
Percentage of OperatingIncomeLoss180.5220.1141.7164.1268.0251.5179.2205.8220.0408.3166.5307.0347.71037.1741.7-99.9620.5180.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax11.811.113.714.79.210.612.312.111.09.811.611.010.010.014.810.816.324.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments synh:ClinicalSolutionsSegment15.214.30.019.512.514.10.016.515.013.60.014.913.613.40.00.00.025.2

us-gaap:OperatingSegments, synh:CommercialSolutionsSegment


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value372946363825493738355239342935250.150.346
Percentage of OperatingIncomeLoss44.848.842.237.2109.551.960.053.766.9131.066.199.9110.8286.4233.4-29.01.51.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.92.54.13.33.82.24.13.23.33.14.63.63.22.84.73.10.00.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments synh:CommercialSolutionsSegment12.911.00.013.614.48.80.012.012.311.20.013.511.810.80.00.00.013.4

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

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax

us-gaap:AccumulatedOtherComprehensiveIncome


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value4.7085.9375.219-1.131-10.735.5080.074-8.962-4.216
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.40.50.5-0.1-0.90.50.0-0.8-0.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.0

Other Nonoperating Income Expense

us-gaap:OtherNonoperatingIncomeExpense

us-gaap:OtherNonoperatingIncomeExpense


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-7.8279.8560.403-10.596-5.761-18.93-53.527307.573-8.92113-4.34632-12.554-3.682-5.953-6.754-3.4571.759-2.384-3.26-5.117-0.281-1.0031.6753.4661.5125.136-0.3371.378
Percentage of OtherNonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.60.80.0-1.0-0.6-1.6-4.42.60.6-0.81.1-0.43.0-1.2-0.5-0.7-1.7-1.40.7-0.6-0.8-1.2-0.1-0.30.51.10.71.7-0.10.5

Revenue From Contract With Customer Excluding Assessed Tax

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value12821208114010991013116312121177116611191145111410721057750822391252262391399413241350337308213298285266174169159149
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, synh:ClinicalSolutionsSegment


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-03-31
Value991937855829747874899867849804821819783786249
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax77.377.675.075.473.775.274.173.772.871.971.773.573.174.499.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax77.377.675.075.473.775.274.173.772.871.971.773.573.174.499.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments synh:ClinicalSolutionsSegment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, synh:CommercialSolutionsSegment


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-03-31
Value2912702842692662883133093163143242952882702.581
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax22.722.425.024.626.324.825.926.327.228.128.326.526.925.61.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax22.722.425.024.626.324.825.926.327.228.128.326.526.925.61.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments synh:CommercialSolutionsSegment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:StatementGeographical

country:US


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-03-31
Value722693658659608713739745741704715718690696323445193178195208194180173165163147130
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax56.457.457.760.060.161.360.963.363.562.962.464.464.465.943.154.149.670.874.353.148.643.771.747.448.447.948.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax56.457.457.760.060.161.360.963.363.562.962.464.464.465.943.154.149.670.874.353.148.643.771.747.448.447.948.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax country:US100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

srt:AsiaPacific


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value14412611612111011711911994111105979377
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax11.210.510.211.010.910.19.910.18.110.09.38.88.77.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax11.210.510.211.010.910.19.910.18.110.09.38.88.77.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:AsiaPacific100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

srt:LatinAmerica


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value3527262422252625222122222018
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.72.22.32.32.22.22.22.21.91.92.02.11.91.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.72.22.32.32.22.22.22.21.91.92.02.11.91.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:LatinAmerica100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

srt:NorthAmerica


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value774739705694638753780780791727754761726731
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax60.461.161.963.263.064.764.366.367.865.065.968.367.769.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax60.461.161.963.263.064.764.366.367.865.065.968.367.769.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NorthAmerica100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EMEA


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value328316291258242268286251258258262232232228244984657523751565458555558555447
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax25.626.225.523.523.923.023.621.422.223.122.920.921.621.632.612.011.922.720.19.513.013.822.516.616.417.927.218.519.217.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax25.626.225.523.523.923.023.621.422.223.122.920.921.621.632.612.011.922.720.19.513.013.822.516.616.417.927.218.519.217.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:EMEA100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Selling General And Administrative Expense

us-gaap:SellingGeneralAndAdministrativeExpense

us-gaap:SellingGeneralAndAdministrativeExpense


Selling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value1441371081111041171121091101131099610099106884244444142434340373540383332
Percentage of SellingGeneralAndAdministrativeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax11.311.49.510.110.410.19.39.39.510.19.68.79.39.414.210.810.917.816.910.710.710.517.911.511.011.619.112.811.912.1

us-gaap:SellingGeneralAndAdministrativeExpense us-gaap:ConsolidationItems

us-gaap:CorporateNonSegment


Selling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value26208.38516131112131411146.4797.6389.7596.6849.4353.9785.0385.1223.439
Percentage of SellingGeneralAndAdministrativeExpense18.515.07.714.512.79.511.112.713.110.013.56.77.69.86.310.69.411.211.58.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.11.70.71.51.31.01.01.21.21.01.30.60.70.90.91.11.02.01.90.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CorporateNonSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments


Selling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value109108968783989290899591858985947735363636
Percentage of SellingGeneralAndAdministrativeExpense75.879.088.778.979.683.982.182.081.084.783.388.689.686.188.586.982.981.983.087.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax8.59.08.48.08.28.57.67.77.78.68.07.78.48.112.59.49.014.614.19.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:SellingGeneralAndAdministrativeExpense us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, synh:ClinicalSolutionsSegment


Selling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value898773666374696867696863686571593536
Percentage of SellingGeneralAndAdministrativeExpense61.763.767.959.860.263.262.062.561.061.662.465.768.066.467.766.682.981.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax7.07.26.56.06.26.45.75.85.86.26.05.76.46.29.67.29.014.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments synh:ClinicalSolutionsSegment9.09.38.68.08.58.57.77.98.08.78.47.88.78.40.00.00.014.7

us-gaap:OperatingSegments, synh:CommercialSolutionsSegment


Selling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value202022212024222122262222211922180.00.0
Percentage of SellingGeneralAndAdministrativeExpense14.015.320.819.119.520.720.119.520.023.020.922.921.619.720.820.40.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.61.72.01.92.02.11.91.81.92.32.02.02.01.82.92.20.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments synh:CommercialSolutionsSegment7.07.77.97.87.78.57.26.97.08.37.17.57.57.20.00.00.00.0

Assets

us-gaap:Assets

us-gaap:Assets


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value8019795480637384740775907453737773967387725472097173724172857296133612911288124412521228121113031215127612451233
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Liabilities

us-gaap:Liabilities

us-gaap:Liabilities


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value4781471748214288440746124424450945734549439843764350433442634270982956987982963976993985935867852956
Percentage of Liabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets59.659.359.858.159.560.859.461.161.861.660.660.760.659.958.558.573.674.076.679.076.979.582.075.676.968.068.577.6

Liabilities And Stockholders Equity

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:LiabilitiesAndStockholdersEquity


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value8019795480637384740775907453737773967387725472097173724172857296133612911288124412521228121113031215127612451233
Percentage of LiabilitiesAndStockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-312012-12-312011-12-31
Value3238323632423096299929773029286728232838285628332822290730223026353335301261288252217317280408392276316379
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets40.440.740.241.940.539.240.638.938.238.439.439.339.440.141.541.526.426.023.421.023.120.518.024.423.132.031.522.40.00.0

us-gaap:StockholdersEquity us-gaap:StatementEquityComponents

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Stockholders
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-8.116-12.824-18.761-21.478-26.697-25.566-14.836-20.344-20.418-11.456-7.24
Percentage of StockholdersEquity-0.3-0.4-0.6-0.7-0.9-0.9-0.5-0.7-0.7-0.4-0.3
Percentage of Assets-0.1-0.2-0.2-0.3-0.4-0.3-0.2-0.3-0.3-0.2-0.1
Percentage of Assets us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-01-012015-12-312014-12-312013-12-312012-12-312011-12-31
Value-25.641-39.174-40.801-90.321-129.372-131.111-71.593-127.035-92.688-71.807-88.195-53.735-55.06415-22.385-25.54-30.051-37.254-42.25-36.649-38.399-41.543-41.543-26.2-9.841-9.911-7.966
Percentage of StockholdersEquity-0.8-1.2-1.3-2.9-4.3-4.4-2.4-4.4-3.3-2.5-3.1-1.9-2.00.5-0.7-0.8-8.5-11.1-14.0-14.0-13.30.0-19.1-6.7-3.6-3.1-2.1
Percentage of Assets-0.3-0.5-0.5-1.2-1.7-1.7-1.0-1.7-1.3-1.0-1.2-0.7-0.80.2-0.3-0.4-2.2-2.9-3.3-2.9-3.10.0-3.4-2.1-0.80.00.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedTranslationAdjustment


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value-17.525-26.35-22.04-68.843-102.675-105.545-56.757-106.691-72.27-60.351-80.955-56.461-55.16614-23.514-26.398-31.024-38.51-43.356-36.495-37.476-41.543
Percentage of StockholdersEquity-0.5-0.8-0.7-2.2-3.4-3.5-1.9-3.7-2.6-2.1-2.8-2.0-2.00.5-0.8-0.9-8.8-11.5-14.4-13.9-13.0-19.1
Percentage of Assets-0.2-0.3-0.3-0.9-1.4-1.4-0.8-1.4-1.0-0.8-1.1-0.8-0.80.2-0.3-0.4-2.3-3.0-3.4-2.9-3.0-3.4
Percentage of Assets us-gaap:AccumulatedTranslationAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312016-01-012015-12-312014-12-312013-12-312012-12-312011-12-31
Value343034403461345434463430344134253404340234023390337133943414573559559634480477476
Percentage of StockholdersEquity105.9106.3106.8111.6114.9115.2113.6119.5120.6119.9119.1119.7119.4116.8113.0190.10.0257.5161.9174.0150.8125.5
Percentage of Assets42.843.342.946.846.545.246.246.446.046.146.947.047.046.946.944.50.046.251.039.00.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312016-01-012015-12-312014-12-312013-12-312012-12-312011-12-31
Value1.0351.0421.0391.041.0421.0421.0391.0381.0351.0381.0341.0321.0291.0381.0440.5380.5390.5390.6121.0511.0511.05
Percentage of StockholdersEquity0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.20.00.20.20.40.30.3
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.10.00.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312016-01-012015-12-312014-12-312013-12-312012-12-312011-12-31
Value-167.155-165.831-179.873-268.622-318.838-322.749-341.263-432.313-488.837-493.814-459.333-505.003-494.609-504.187-370.469-229.991-293.918-301.472-217.149-188.831-146.802-87.188
Percentage of StockholdersEquity-5.2-5.1-5.5-8.7-10.6-10.8-11.3-15.1-17.3-17.4-16.1-17.8-17.5-17.3-12.3-76.30.0-138.6-55.4-68.4-46.3-23.0
Percentage of Assets-2.1-2.1-2.2-3.6-4.3-4.3-4.6-5.9-6.6-6.7-6.3-7.0-6.9-7.0-5.1-17.80.0-24.9-17.4-15.30.00.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Assets Current

us-gaap:AssetsCurrent

us-gaap:AssetsCurrent


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value1748167417381595159717741562149214661407149113561417138814221362582539522487484450422521426477426376
Percentage of AssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets21.821.021.621.621.623.421.020.219.819.120.618.819.819.219.518.743.641.740.639.138.736.634.840.035.137.434.330.5

Cash And Cash Equivalents At Carrying Value

us-gaap:CashAndCashEquivalentsAtCarryingValue us-gaap:ConcentrationRiskByType, us-gaap:GeographicDistribution

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:CustomerConcentrationRisk, us-gaap:GeographicDistributionForeign


Cash
Period End2021-06-302020-12-31
Value14550
Percentage of CashAndCashEquivalentsAtCarryingValue100.0100.0
Percentage of Assets1.80.6
Percentage of Assets us-gaap:CustomerConcentrationRisk us-gaap:GeographicDistributionForeign0.00.0

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-31
Value26126427224834333516312910710715513417318832130517016510385
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.33.33.43.44.64.42.21.81.41.52.11.92.42.64.44.212.712.88.07.1

Prepaid Expense And Other Assets Current

us-gaap:PrepaidExpenseAndOtherAssetsCurrent

us-gaap:PrepaidExpenseAndOtherAssetsCurrent


Prepaid
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value11711012182809794687178798082948496372734363533383734303535
Percentage of PrepaidExpenseAndOtherAssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.51.41.51.11.11.31.30.91.01.11.11.11.21.31.21.32.82.12.72.92.92.73.22.92.82.42.82.9

Property Plant And Equipment Gross

us-gaap:PropertyPlantAndEquipmentGross

us-gaap:PropertyPlantAndEquipmentGross


Property
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302016-12-312015-12-312014-12-312013-12-31
Value467409337277250121928293
Percentage of PropertyPlantAndEquipmentGross100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets5.85.54.73.83.49.57.66.77.6

us-gaap:PropertyPlantAndEquipmentGross us-gaap:PropertyPlantAndEquipmentByType

synh:AssetsNotYetPlacedInService


Property
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value2820112913
Percentage of PropertyPlantAndEquipmentGross6.04.93.310.511.0
Percentage of Assets0.30.30.20.41.0
Percentage of Assets synh:AssetsNotYetPlacedInService0.00.00.00.00.0

us-gaap:BuildingAndBuildingImprovements


Property
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302016-12-312015-12-31
Value5.2114.2564.3484.5524.4854.0044.597
Percentage of PropertyPlantAndEquipmentGross1.11.01.31.61.83.35.0
Percentage of Assets0.10.10.10.10.10.30.4
Percentage of Assets us-gaap:BuildingAndBuildingImprovements0.00.00.00.00.00.00.0

us-gaap:ComputerEquipment


Property
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302016-12-312015-12-312014-12-312013-12-31
Value1089582615626232026
Percentage of PropertyPlantAndEquipmentGross23.223.324.422.222.421.625.824.828.8
Percentage of Assets1.31.31.10.80.82.02.01.72.2
Percentage of Assets us-gaap:ComputerEquipment0.00.00.00.00.00.00.00.00.0

us-gaap:FurnitureAndFixtures


Property
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302016-12-312015-12-312014-12-312013-12-31
Value3733241920109.1738.3017.346
Percentage of PropertyPlantAndEquipmentGross8.08.27.17.08.18.910.010.07.9
Percentage of Assets0.50.40.30.30.30.80.80.70.6
Percentage of Assets us-gaap:FurnitureAndFixtures0.00.00.00.00.00.00.00.00.0

us-gaap:LeaseholdImprovements


Property
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302016-12-312015-12-312014-12-312013-12-31
Value948669585314131210
Percentage of PropertyPlantAndEquipmentGross20.221.120.621.221.312.115.115.010.8
Percentage of Assets1.21.21.00.80.71.11.11.00.8
Percentage of Assets us-gaap:LeaseholdImprovements0.00.00.00.00.00.00.00.00.0

us-gaap:SoftwareAndSoftwareDevelopmentCosts


Property
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302016-12-312015-12-312014-12-312013-12-31
Value1299991656452333038
Percentage of PropertyPlantAndEquipmentGross27.824.327.023.425.843.136.037.141.3
Percentage of Assets1.61.31.30.90.94.12.72.53.1
Percentage of Assets us-gaap:SoftwareAndSoftwareDevelopmentCosts0.00.00.00.00.00.00.00.00.0

us-gaap:Vehicles


Property
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302016-12-31
Value63705538370.0
Percentage of PropertyPlantAndEquipmentGross13.717.216.414.014.90.0
Percentage of Assets0.80.90.80.50.50.0
Percentage of Assets us-gaap:Vehicles0.00.00.00.00.00.0

Accumulated Depreciation Depletion And Amortization Property Plant And Equipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment


Accumulated
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302016-12-312015-12-312014-12-312013-12-31
Value250205154977763473952
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.12.82.11.31.14.93.93.14.2

Amortization Of Intangible Assets

us-gaap:AmortizationOfIntangibleAssets

us-gaap:AmortizationOfIntangibleAssets


Amortization
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value393936383838414141415150494965519.4629.4649.4639.4649.4639.4619.4619.4629.4739.4789.5879.5976.2387.502
Percentage of AmortizationOfIntangibleAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Property Plant And Equipment Net

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:PropertyPlantAndEquipmentNet


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value203202216196197195203201187175183175163173180172585758454645443940414340
Percentage of PropertyPlantAndEquipmentNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.52.52.72.72.72.62.72.72.52.42.52.42.32.42.52.44.44.54.53.73.73.73.73.03.33.33.53.3

us-gaap:PropertyPlantAndEquipmentNet us-gaap:StatementGeographical

country:US


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value14414515614314614815315113412312812311312012812340
Percentage of PropertyPlantAndEquipmentNet70.872.072.273.374.575.775.175.171.669.969.970.569.769.671.271.469.6
Percentage of Assets1.81.81.91.92.01.92.12.01.81.71.81.71.61.71.81.73.2
Percentage of Assets country:US0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

srt:AsiaPacific


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value109.392111111111213141213121214
Percentage of PropertyPlantAndEquipmentNet5.24.65.25.85.75.96.26.87.67.27.37.37.58.1
Percentage of Assets0.10.10.10.20.20.20.20.20.20.20.20.20.20.2
Percentage of Assets srt:AsiaPacific0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

srt:LatinAmerica


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value5.7595.1074.7574.2383.4162.6982.9612.933.2323.363.5123.8073.8044.094
Percentage of PropertyPlantAndEquipmentNet2.82.52.22.21.71.41.51.51.71.91.92.22.32.3
Percentage of Assets0.10.10.10.10.00.00.00.00.00.00.00.10.10.1
Percentage of Assets srt:LatinAmerica0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

srt:NorthAmerica


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value150151161149152153159156139128133129120136
Percentage of PropertyPlantAndEquipmentNet73.774.874.776.277.578.778.377.874.573.072.874.073.675.4
Percentage of Assets1.91.92.02.02.12.02.12.11.91.71.81.81.71.9
Percentage of Assets srt:NorthAmerica0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:EMEA


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value3736383129272828303133282627252511
Percentage of PropertyPlantAndEquipmentNet18.318.017.915.815.114.014.013.916.117.918.016.516.516.014.114.919.3
Percentage of Assets0.50.50.50.40.40.40.40.40.40.40.50.40.40.40.40.40.9
Percentage of Assets us-gaap:EMEA0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Goodwill

us-gaap:Goodwill

us-gaap:Goodwill


Goodwill
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-312012-12-31
Value4789478047764343432343234350432243364344433343524275430642924265553553552553552553553552553553556563565
Percentage of Goodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets59.760.159.258.858.457.058.458.658.658.859.760.459.659.558.958.541.442.842.944.444.245.045.742.445.543.444.745.70.0

us-gaap:Goodwill us-gaap:BusinessAcquisition

synh:IllingworthResearch


Goodwillus-gaap:
Period End2020-12-17
Value62
Percentage of Goodwill0.0
Percentage of Assets0.0
Percentage of Assets synh:IllingworthResearch0.0

synh:SynteractAcquisition


Goodwillus-gaap:
Period End2020-12-09
Value355
Percentage of Goodwill0.0
Percentage of Assets0.0
Percentage of Assets synh:SynteractAcquisition0.0

us-gaap:Goodwill us-gaap:BusinessAcquisition, us-gaap:StatementBusinessSegments

synh:SynteractAcquisition, synh:ClinicalSolutionsSegment


Goodwillus-gaap:
Period End2020-12-09
Value355
Percentage of Goodwill0.0
Percentage of Assets0.0
Percentage of Assets synh:SynteractAcquisition synh:ClinicalSolutionsSegment0.0

us-gaap:Goodwill us-gaap:StatementBusinessSegments

synh:ClinicalSolutionsSegment


Goodwillus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-31
Value327632673216277827642764278427632774278127722782278628102800552553
Percentage of Goodwill68.468.467.364.063.963.964.063.964.064.064.063.965.265.365.2100.0100.0
Percentage of Assets40.941.139.937.637.336.437.437.537.537.738.238.638.838.838.442.945.7
Percentage of Assets synh:ClinicalSolutionsSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

synh:CommercialSolutionsSegment


Goodwillus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-31
Value1512151215591565155815581565155815621563156015701488149614910.00.0
Percentage of Goodwill31.631.632.736.036.136.136.036.136.036.036.036.134.834.734.80.00.0
Percentage of Assets18.919.019.321.221.020.521.021.121.121.221.521.820.820.720.50.00.0
Percentage of Assets synh:CommercialSolutionsSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Intangible Assets Net Excluding Goodwill

us-gaap:IntangibleAssetsNetExcludingGoodwill

us-gaap:IntangibleAssetsNetExcludingGoodwill


Intangible
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value83189693388291392597310041051109611331189118212411286139495105114124133142152161171180190231
Percentage of IntangibleAssetsNetExcludingGoodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets10.411.311.612.012.312.213.113.614.214.815.616.516.517.117.719.17.28.18.910.010.711.612.612.414.114.215.318.7

Finite Lived Intangible Assets Net

us-gaap:FiniteLivedIntangibleAssetsNet

us-gaap:FiniteLivedIntangibleAssetsNet


Finite
Period End2020-12-312019-12-312018-12-312018-09-302017-12-312017-09-302017-03-312016-12-312015-12-312014-12-312013-12-31
Value9339731133118912861394128679117155196
Percentage of FiniteLivedIntangibleAssetsNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets11.613.115.616.517.719.199.66.29.712.515.9

us-gaap:FiniteLivedIntangibleAssetsNet us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:CustomerRelationships


Finite
Period End2020-12-312019-12-312018-12-312018-09-302017-12-312017-09-302016-12-312015-12-312014-12-312013-12-31
Value833944108011201174114279117155194
Percentage of FiniteLivedIntangibleAssetsNet89.297.095.394.291.381.9100.0100.0100.099.2
Percentage of Assets10.312.714.915.516.115.76.29.712.515.8
Percentage of Assets us-gaap:CustomerRelationships0.00.00.00.00.00.00.00.00.00.0

us-gaap:IntellectualProperty


Finite
Period End2020-12-31
Value28
Percentage of FiniteLivedIntangibleAssetsNet3.0
Percentage of Assets0.4
Percentage of Assets us-gaap:IntellectualProperty0.0

us-gaap:OrderOrProductionBacklog


Finite
Period End2020-12-312019-12-312018-12-312018-09-302017-12-312017-09-302016-12-312015-12-312014-12-312013-12-31
Value41153550952250.00.00.01.35
Percentage of FiniteLivedIntangibleAssetsNet4.41.63.14.27.416.20.00.00.00.7
Percentage of Assets0.50.20.50.71.33.10.00.00.00.1
Percentage of Assets us-gaap:OrderOrProductionBacklog0.00.00.00.00.00.00.00.00.00.0

us-gaap:TrademarksAndTradeNames


Finite
Period End2020-12-312019-12-31
Value3013
Percentage of FiniteLivedIntangibleAssetsNet3.31.4
Percentage of Assets0.40.2
Percentage of Assets us-gaap:TrademarksAndTradeNames0.00.0

Intangible Assets Net Including Goodwill

us-gaap:IntangibleAssetsNetIncludingGoodwill us-gaap:FairValueByMeasurementFrequency

us-gaap:IntangibleAssetsNetIncludingGoodwill

us-gaap:FairValueMeasurementsNonrecurring


Intangible
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-31
Value5650568057105230524052505320533053905440547055405460555055785659667705
Percentage of IntangibleAssetsNetIncludingGoodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets70.571.470.870.870.769.271.472.272.973.675.476.876.176.676.677.651.858.2
Percentage of Assets us-gaap:FairValueMeasurementsNonrecurring0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Deferred Tax Assets Liabilities Net

us-gaap:DeferredTaxAssetsLiabilitiesNet

us-gaap:DeferredTaxAssetsLiabilitiesNet


Deferred
Period End2020-12-312019-12-312014-12-312013-12-31
Value14251.155-11.743
Percentage of DeferredTaxAssetsLiabilitiesNet100.0100.0100.0100.0
Percentage of Assets0.20.30.1-1.0

Operating Lease Right Of Use Asset

us-gaap:OperatingLeaseRightOfUseAsset

us-gaap:OperatingLeaseRightOfUseAsset


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value2222152232132112182182202272390.0
Percentage of OperatingLeaseRightOfUseAsset100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets2.82.72.82.92.92.92.93.03.13.20.0

Other Assets Noncurrent

us-gaap:OtherAssetsNoncurrent

us-gaap:OtherAssetsNoncurrent


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value1861511411351301181081311181131031021011048480191825232324261111111117
Percentage of OtherAssetsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.31.91.71.81.81.61.51.81.61.51.41.41.41.41.21.11.51.42.01.91.92.02.20.90.90.90.91.4

Accounts Payable Current

us-gaap:AccountsPayableCurrent

us-gaap:AccountsPayableCurrent


Accounts
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value10711311310492112136821289498828569586626182322274022141414169.594
Percentage of AccountsPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.31.41.41.41.21.51.81.11.71.31.41.11.21.00.80.92.01.51.81.82.23.31.91.11.21.11.30.8

Accrued Liabilities Current

us-gaap:AccruedLiabilitiesCurrent

us-gaap:AccruedLiabilitiesCurrent


Accrued
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value6255876115835325045685875695355635275025185004451581331531461471441111101009711194
Percentage of AccruedLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets7.87.47.67.97.26.67.68.07.77.27.87.37.07.26.96.111.810.311.911.711.811.89.28.58.27.69.07.6

Contract With Customer Liability Current

us-gaap:ContractWithCustomerLiabilityCurrent

us-gaap:ContractWithCustomerLiabilityCurrent


Contract
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value802773793710657689696703710713777709719643559
Percentage of ContractWithCustomerLiabilityCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets10.09.79.89.68.99.19.39.59.69.710.79.810.08.97.7

Liabilities Current

us-gaap:LiabilitiesCurrent

us-gaap:LiabilitiesCurrent


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value1596153215771511142614411516145116541383150313971361127811591073507458466482474472474462412398379318
Percentage of LiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets19.919.319.620.519.319.020.319.722.418.720.719.419.017.715.914.738.035.536.238.837.938.539.235.533.931.230.525.8

Long Term Debt Current

us-gaap:LongTermDebtCurrent

us-gaap:LongTermDebtCurrent


Long
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value56877758281990.050623731253023171130155.781290.00.04.254.254.713
Percentage of LongTermDebtCurrent100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0
Percentage of Assets0.81.21.00.80.42.70.00.70.90.50.40.30.41.81.40.92.51.20.52.50.00.00.30.30.4

Operating Lease Liability Current

us-gaap:OperatingLeaseLiabilityCurrent

us-gaap:OperatingLeaseLiabilityCurrent


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-06-302018-12-31
Value43404239404038290.0
Percentage of OperatingLeaseLiabilityCurrent100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets0.50.50.50.50.60.50.50.40.0

Other Accrued Liabilities Current

us-gaap:OtherAccruedLiabilitiesCurrent

us-gaap:OtherAccruedLiabilitiesCurrent


Other
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302016-12-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value454545535729161721191613
Percentage of OtherAccruedLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.60.60.60.70.82.31.41.41.71.51.31.1

Taxes Payable Current

us-gaap:TaxesPayableCurrent

us-gaap:TaxesPayableCurrent


Taxes
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302016-12-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value28173016281.0724.20213109.918103.973
Percentage of TaxesPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.40.20.40.20.40.10.31.00.80.80.90.3

Long Term Debt

us-gaap:LongTermDebt

us-gaap:LongTermDebt


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value28632862290225222740290926082708273427852787
Percentage of LongTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets35.736.036.034.237.038.335.036.737.037.738.4

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

synh:AccountsReceivableSecuritization, synh:AccountsReceivableFinancingAgreementDueSeptember2021, us-gaap:SecuredDebt


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-30
Value365365300300275
Percentage of LongTermDebt12.712.810.311.910.0
Percentage of Assets4.64.63.74.13.7
Percentage of Assets synh:AccountsReceivableSecuritization synh:AccountsReceivableFinancingAgreementDueSeptember2021 us-gaap:SecuredDebt0.00.00.00.00.0

Long Term Debt Noncurrent

us-gaap:LongTermDebtNoncurrent

us-gaap:LongTermDebtNoncurrent


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value2863286229022465265328312550268025342785273727752835290829452984449470485466456466472475475414415587
Percentage of LongTermDebtNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets35.736.036.033.435.837.334.236.334.337.737.738.539.540.240.440.933.636.437.737.536.538.039.036.539.132.533.447.6

Deferred Income Tax Liabilities Net

us-gaap:DeferredIncomeTaxLiabilitiesNet

us-gaap:DeferredIncomeTaxLiabilitiesNet


Deferred
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-31
Value1317207.9319.518.989113333262558322237510.3168.295
Percentage of DeferredIncomeTaxLiabilitiesNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.20.20.30.10.10.10.10.50.40.40.30.80.50.30.50.70.00.6

Other Liabilities Noncurrent

us-gaap:OtherLiabilitiesNoncurrent

us-gaap:OtherLiabilitiesNoncurrent


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value6464686582839085938810612310811099139262526282822192020262722
Percentage of OtherLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.80.80.80.91.11.11.21.21.31.21.51.71.51.51.41.91.92.02.02.32.31.81.61.51.72.12.21.8

Operating Lease Liability Noncurrent

us-gaap:OperatingLeaseLiabilityNoncurrent

us-gaap:OperatingLeaseLiabilityNoncurrent


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-06-302018-12-31
Value2172132212092072152182280.0
Percentage of OperatingLeaseLiabilityNoncurrent100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets2.72.72.82.82.82.82.93.10.0

Lessee Operating Lease Liability Payments Due Year Two

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo


Lessee
Period End2020-12-31
Value51
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearTwo100.0
Percentage of Assets0.6

Lessee Operating Lease Liability Payments Due Year Three

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree


Lessee
Period End2020-12-31
Value45
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearThree100.0
Percentage of Assets0.6

Lessee Operating Lease Liability Payments Due Year Four

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour


Lessee
Period End2020-12-31
Value37
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFour100.0
Percentage of Assets0.5

Lessee Operating Lease Liability Payments Due Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive


Lessee
Period End2020-12-31
Value29
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFive100.0
Percentage of Assets0.4

Lessee Operating Lease Liability Payments Due After Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive


Lessee
Period End2020-12-31
Value99
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive100.0
Percentage of Assets1.2

Operating Lease Liability

us-gaap:OperatingLeaseLiability

us-gaap:OperatingLeaseLiability


Operating
Period End2020-12-312019-09-302019-06-302019-03-31
Value263252258265
Percentage of OperatingLeaseLiability100.0100.0100.0100.0
Percentage of Assets3.33.43.53.6

Lessee Operating Lease Liability Payments Due

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue


Lessee
Period End2020-12-31
Value317
Percentage of LesseeOperatingLeaseLiabilityPaymentsDue100.0
Percentage of Assets3.9

Lessee Operating Lease Liability Undiscounted Excess Amount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount


Lessee
Period End2020-12-31
Value53
Percentage of LesseeOperatingLeaseLiabilityUndiscountedExcessAmount100.0
Percentage of Assets0.7

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-312012-12-312011-12-31
Value3238323632423096299929773029286728232838285628332822290730223026353335301261288252217317280408392276316379
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets40.440.740.241.940.539.240.638.938.238.439.439.339.440.141.541.526.426.023.421.023.120.518.024.423.132.031.522.40.00.0

us-gaap:StockholdersEquity us-gaap:StatementEquityComponents

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Stockholders
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-8.116-12.824-18.761-21.478-26.697-25.566-14.836-20.344-20.418-11.456-7.24
Percentage of StockholdersEquity-0.3-0.4-0.6-0.7-0.9-0.9-0.5-0.7-0.7-0.4-0.3
Percentage of Assets-0.1-0.2-0.2-0.3-0.4-0.3-0.2-0.3-0.3-0.2-0.1
Percentage of Assets us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-01-012015-12-312014-12-312013-12-312012-12-312011-12-31
Value-25.641-39.174-40.801-90.321-129.372-131.111-71.593-127.035-92.688-71.807-88.195-53.735-55.06415-22.385-25.54-30.051-37.254-42.25-36.649-38.399-41.543-41.543-26.2-9.841-9.911-7.966
Percentage of StockholdersEquity-0.8-1.2-1.3-2.9-4.3-4.4-2.4-4.4-3.3-2.5-3.1-1.9-2.00.5-0.7-0.8-8.5-11.1-14.0-14.0-13.30.0-19.1-6.7-3.6-3.1-2.1
Percentage of Assets-0.3-0.5-0.5-1.2-1.7-1.7-1.0-1.7-1.3-1.0-1.2-0.7-0.80.2-0.3-0.4-2.2-2.9-3.3-2.9-3.10.0-3.4-2.1-0.80.00.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedTranslationAdjustment


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value-17.525-26.35-22.04-68.843-102.675-105.545-56.757-106.691-72.27-60.351-80.955-56.461-55.16614-23.514-26.398-31.024-38.51-43.356-36.495-37.476-41.543
Percentage of StockholdersEquity-0.5-0.8-0.7-2.2-3.4-3.5-1.9-3.7-2.6-2.1-2.8-2.0-2.00.5-0.8-0.9-8.8-11.5-14.4-13.9-13.0-19.1
Percentage of Assets-0.2-0.3-0.3-0.9-1.4-1.4-0.8-1.4-1.0-0.8-1.1-0.8-0.80.2-0.3-0.4-2.3-3.0-3.4-2.9-3.0-3.4
Percentage of Assets us-gaap:AccumulatedTranslationAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312016-01-012015-12-312014-12-312013-12-312012-12-312011-12-31
Value343034403461345434463430344134253404340234023390337133943414573559559634480477476
Percentage of StockholdersEquity105.9106.3106.8111.6114.9115.2113.6119.5120.6119.9119.1119.7119.4116.8113.0190.10.0257.5161.9174.0150.8125.5
Percentage of Assets42.843.342.946.846.545.246.246.446.046.146.947.047.046.946.944.50.046.251.039.00.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312016-01-012015-12-312014-12-312013-12-312012-12-312011-12-31
Value1.0351.0421.0391.041.0421.0421.0391.0381.0351.0381.0341.0321.0291.0381.0440.5380.5390.5390.6121.0511.0511.05
Percentage of StockholdersEquity0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.20.00.20.20.40.30.3
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.10.00.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312016-01-012015-12-312014-12-312013-12-312012-12-312011-12-31
Value-167.155-165.831-179.873-268.622-318.838-322.749-341.263-432.313-488.837-493.814-459.333-505.003-494.609-504.187-370.469-229.991-293.918-301.472-217.149-188.831-146.802-87.188
Percentage of StockholdersEquity-5.2-5.1-5.5-8.7-10.6-10.8-11.3-15.1-17.3-17.4-16.1-17.8-17.5-17.3-12.3-76.30.0-138.6-55.4-68.4-46.3-23.0
Percentage of Assets-2.1-2.1-2.2-3.6-4.3-4.3-4.6-5.9-6.6-6.7-6.3-7.0-6.9-7.0-5.1-17.80.0-24.9-17.4-15.30.00.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Common Stock Value

us-gaap:CommonStockValue

us-gaap:CommonStockValue


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value1035000.01042000.01039000.01040000.01042000.01042000.01039000.01038000.01035000.01038000.01034000.01032000.01029000.01038000.01044000.01042000.0542000.0541000.0538000.0536000.0546000.0540000.0539000.0565000.0563000.0612000.0612000.01051000.0
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.1

Additional Paid In Capital

us-gaap:AdditionalPaidInCapital

us-gaap:AdditionalPaidInCapital


Additional
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value3430344034613454344634303441342534043402340233903371339434143404590582573565572564559584583635634480
Percentage of AdditionalPaidInCapital100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets42.843.342.946.846.545.246.246.446.046.146.947.047.046.946.946.744.245.144.545.445.745.946.244.848.049.851.039.0

Retained Earnings Accumulated Deficit

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:RetainedEarningsAccumulatedDeficit


Retained
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value-167160000.0-165830000.0-179870000.0-268620000.0-318840000.0-322750000.0-341260000.0-432310000.0-488840000.0-493810000.0-459330000.0-505000000.0-494610000.0-504190000.0-370470000.0-353700000.0-207420000.0-210810000.0-229990000.0-267480000.0-246110000.0-276510000.0-301470000.0-228240000.0-266050000.0-191890000.0-217150000.0-188830000.0
Percentage of RetainedEarningsAccumulatedDeficit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets-2.1-2.1-2.2-3.6-4.3-4.3-4.6-5.9-6.6-6.7-6.3-7.0-6.9-7.0-5.1-4.8-15.5-16.3-17.8-21.5-19.7-22.5-24.9-17.5-21.9-15.0-17.4-15.3

Accumulated Other Comprehensive Income Loss Net Of Tax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value-25.641-39.174-40.801-90.321-129.372-131.111-71.593-127.035-92.688-71.807-88.195-53.735-55.06415-22.385-25.54-30.051-37.254-42.25-36.649-38.399-36.207-41.543-38.474-37.594-35.418-26.2-9.841
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets-0.3-0.5-0.5-1.2-1.7-1.7-1.0-1.7-1.3-1.0-1.2-0.7-0.80.2-0.3-0.4-2.2-2.9-3.3-2.9-3.1-2.9-3.4-3.0-3.1-2.8-2.1-0.8

Stock Issued During Period Value New Issues

us-gaap:StockIssuedDuringPeriodValueNewIssues us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodValueNewIssues

us-gaap:AdditionalPaidInCapital


Stock
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value2.874-18.4431.1249.231-0.063-6.9951.316134.377
Percentage of StockIssuedDuringPeriodValueNewIssues100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stock
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value0.0020.0090.0010.0030.00.0090.0010.0040.002
Percentage of StockIssuedDuringPeriodValueNewIssues0.1-0.00.10.0-0.0-0.10.10.00.0
Percentage of Assets0.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.0

Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue us-gaap:StatementEquityComponents

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue

us-gaap:AdditionalPaidInCapital


Adjustments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value161711151615141213148.2789.7918.3757.879
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value88127114156193-38.6071607496-13.306112125112-46.98588112275145045-0.6466345514314364931
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax6.910.510.014.219.1-3.313.26.38.3-1.29.811.310.5-4.411.81.45.830.05.413.011.3-0.226.413.115.314.16.612.417.211.7

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-11499000.0-19781000.0-458730000.0-8072000.0-18660000.0-18620000.0-21789000.0-28806000.0-19621000.0-11445000.0-11632000.0-101270000.0-11300000.0-21286000.0-15928000.0-1691000000.0-5403000.0-10571000.0-14527000.0-5336000.0-6716000.0-4774000.0-9546000.0-3896000.0-2799000.0-4870000.0-7812000.0-4800000.0-8315000.0-6926000.0
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.9-1.6-40.2-0.7-1.8-1.6-1.8-2.4-1.7-1.0-1.0-9.1-1.1-2.0-2.1-205.6-1.4-4.2-5.5-1.4-1.7-1.2-4.0-1.1-0.8-1.6-3.7-1.6-2.9-2.6

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-79.457-111.366366-244.414-173.68229-91.584-23.97-73.577-26.338-72.679-66.983-109.817-69.877-55.881810-13.908-6.023.462-35.8665.54-26.452-102.015-1.991-106.131-1.262-59.485-0.89-0.932-6.391
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-6.2-9.232.1-22.2-17.119.8-7.6-2.0-6.3-2.4-6.3-6.0-10.2-6.6-7.4220.1-3.6-2.41.3-9.21.4-6.4-42.3-0.6-31.5-0.4-27.8-0.3-0.3-2.4

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

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-3.554-7.48423-94.1347.071723421-0.665-48.01121-39.115-15.236-133.021161355.2561
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.3-0.62.0-8.60.714.82.81.9-0.1-4.31.9-3.5-1.4-12.62.216.41.324.6

Amortization Of Financing Costs

us-gaap:AmortizationOfFinancingCosts

us-gaap:AmortizationOfFinancingCosts


Amortization
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value1000.04000.071000.00-159000.01582000.01732000.02241000.00409000.01317000.00
Percentage of AmortizationOfFinancingCosts100.0100.0100.00.0100.0100.0100.0100.00.0100.0100.00.0

Deferred Income Tax Expense Benefit

us-gaap:DeferredIncomeTaxExpenseBenefit

us-gaap:DeferredIncomeTaxExpenseBenefit


Deferred
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-8.371-4.653-25.145120.5918.159-53.164.2987.2491.5440.9616.9613.053-10.7351.69821-9.1680.087-17.0340.105-4.063-1.2684.0220.395-1.2220.9397.3960.209-22.9550.513
Percentage of DeferredIncomeTaxExpenseBenefit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Depreciation Depletion And Amortization

us-gaap:DepreciationDepletionAndAmortization

us-gaap:DepreciationDepletionAndAmortization


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value57575455565660606061706867688365151515
Percentage of DepreciationDepletionAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Increase Decrease In Other Operating Capital Net

us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet

us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value215.0392422-6.52215-19.40216-10.386130.798-17.852-9.278-7.5210.041-11.40610-2.673-9.849-1.1162.741-5.5963.8365.038.672-2.683-3.3151.7233.115-2.743
Percentage of IncreaseDecreaseInOtherOperatingCapitalNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value88127114156193-38.6071607496-13.306112125112-46.98588112275145045-0.6466345514314364931
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax6.910.510.014.219.1-3.313.26.38.3-1.29.811.310.5-4.411.81.45.830.05.413.011.3-0.226.413.115.314.16.612.417.211.7

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value413891633.91133915811-30.00445-10.39413-24.552-15.047-147.9983.389213727301730372325-49.781215-1.552-12.979-1.17-10.634-16.746
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.33.28.15.80.42.97.55.01.0-2.74.0-0.91.3-2.3-2.0-18.00.98.414.37.07.64.212.710.86.98.2-23.34.25.4-0.6-7.4-0.7-6.7-11.2

us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Net
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value4138633.911335811-30.00445-10.39413-24.552
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.33.25.80.42.95.01.0-2.74.0-0.91.3-2.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.0

Share Based Compensation

us-gaap:ShareBasedCompensation

us-gaap:ShareBasedCompensation


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value161711151615141213148.2789.7918.3757.8798.768386.2295.8194.6163.5173.0712.8161.7861.6680.9130.7071.0650.8810.8930.531
Percentage of ShareBasedCompensation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-11499000.0-19781000.0-458730000.0-8072000.0-18660000.0-18620000.0-21789000.0-28806000.0-19621000.0-11445000.0-11632000.0-101270000.0-11300000.0-21286000.0-15928000.0-1691000000.0-5403000.0-10571000.0-14527000.0-5336000.0-6716000.0-4774000.0-9546000.0-3896000.0-2799000.0-4870000.0-7812000.0-4800000.0-8315000.0-6926000.0
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.9-1.6-40.2-0.7-1.8-1.6-1.8-2.4-1.7-1.0-1.0-9.1-1.1-2.0-2.1-205.6-1.4-4.2-5.5-1.4-1.7-1.2-4.0-1.1-0.8-1.6-3.7-1.6-2.9-2.6

Payments To Acquire Property Plant And Equipment

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value1111118.4151811132216111110112115125.40310145.3366.7164.7749.5463.8962.7994.877.8124.88.3154.624
Percentage of PaymentsToAcquirePropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-79.457-111.366366-244.414-173.68229-91.584-23.97-73.577-26.338-72.679-66.983-109.817-69.877-55.881810-13.908-6.023.462-35.8665.54-26.452-102.015-1.991-106.131-1.262-59.485-0.89-0.932-6.391
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-6.2-9.232.1-22.2-17.119.8-7.6-2.0-6.3-2.4-6.3-6.0-10.2-6.6-7.4220.1-3.6-2.41.3-9.21.4-6.4-42.3-0.6-31.5-0.4-27.8-0.3-0.3-2.4

Repayments Of Long Term Debt

us-gaap:RepaymentsOfLongTermDebt

us-gaap:RepaymentsOfLongTermDebt


Repayments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value49610521394190.06711440216362566631504750.00.00.00.00.00.00.00.04731.0631580.00.05.453
Percentage of RepaymentsOfLongTermDebt100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.00.0100.0100.0100.00.00.0100.0

us-gaap:RepaymentsOfLongTermDebt us-gaap:DebtInstrument, us-gaap:LongtermDebtType

synh:A2017CreditAgreementAmendmentNo2TermLoanADueMarch2024, us-gaap:SecuredDebt


Repayments
Period End2021-06-302021-03-312020-09-302019-09-302019-06-302019-03-31
Value0.041400.00.012
Percentage of RepaymentsOfLongTermDebt0.039.542.40.00.05.8

synh:A2017CreditAgreementTermLoanBDueAugust2024, us-gaap:SecuredDebt


Repayments
Period End2021-06-302021-03-312020-09-302018-12-312018-09-30
Value496643530214
Percentage of RepaymentsOfLongTermDebt100.060.637.182.883.3

Payments For Repurchase Of Common Stock

us-gaap:PaymentsForRepurchaseOfCommonStock

us-gaap:PaymentsForRepurchaseOfCommonStock


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-312015-09-302014-12-312014-09-30
Value73448.122300.0320.07.04523260.00.037370.00.00.00.00.0641350.00.00.019
Percentage of PaymentsForRepurchaseOfCommonStock100.0100.0100.0100.00.0100.00.0100.0100.0100.00.00.0100.0100.00.00.00.00.00.0100.0100.00.00.0100.0

Debt Instrument Interest Rate Stated Percentage

us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:DebtInstrumentInterestRateStatedPercentage

synh:SeniorUnsecuredNotesDue2024, us-gaap:UnsecuredDebt


Debt
Period End2020-12-312019-12-312018-12-312017-12-312017-08-01
Value3.6250.0750.0750.0750.075
Percentage of DebtInstrumentInterestRateStatedPercentage100.0100.0100.0100.0100.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations synh:SeniorUnsecuredNotesDue2024 us-gaap:UnsecuredDebt0.00.00.00.00.0

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

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice us-gaap:AwardType

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice

us-gaap:EmployeeStockOption


Share
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302016-12-312015-12-31
Value30.1228.0127.9228.4527.8322.1515.75
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice100.0100.0100.0100.0100.0100.0100.0

Deferred Tax Assets Net

us-gaap:DeferredTaxAssetsNet

us-gaap:DeferredTaxAssetsNet


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value30331324326953437679
Percentage of DeferredTaxAssetsNet100.0100.0100.0100.0100.0100.0100.0100.0

Unrecognized Tax Benefits

us-gaap:UnrecognizedTaxBenefits

us-gaap:UnrecognizedTaxBenefits


Unrecognized
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-312012-12-312011-12-31
Value9.69.59.08.42323231920191919424346151515191920202021232222
Percentage of UnrecognizedTaxBenefits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Deferred Tax Assets Valuation Allowance

us-gaap:DeferredTaxAssetsValuationAllowance

us-gaap:DeferredTaxAssetsValuationAllowance


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value100841501595.238164846
Percentage of DeferredTaxAssetsValuationAllowance100.0100.0100.0100.0100.0100.0100.0100.0

synh:AssetsExchangedInCash

synh:AssetsExchangedInCash


Assets
Period End2021-06-30
Value3900000.0
Percentage of AssetsExchangedInCash100.0

synh:BusinessExitCostsAndGainLossOnTerminationOfLease us-gaap:ValuationAllowancesAndReservesType

synh:BusinessExitCostsAndGainLossOnTerminationOfLease

us-gaap:BusinessRestructuringReserves


Business
Period End2021-06-302021-03-31
Value1900000.0900000.0
Percentage of BusinessExitCostsAndGainLossOnTerminationOfLease100.0100.0

synh:DebtInstrumentCovenantFirstLienLeverageRatioMaximum us-gaap:DebtInstrument, us-gaap:LongtermDebtType

synh:DebtInstrumentCovenantFirstLienLeverageRatioMaximum

synh:A2017CreditAgreementAmendmentNo2RevolvingCreditFacilityDueAugust2024, us-gaap:SecuredDebt


Debt
Period End2021-02-28
Value2.5
Percentage of DebtInstrumentCovenantFirstLienLeverageRatioMaximum100.0

synh:IncomeTaxesDiscreteTaxExpenseBenefits

synh:IncomeTaxesDiscreteTaxExpenseBenefits


Income
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-30
Value2.23.618-1.67.10.1-10.4
Percentage of IncomeTaxesDiscreteTaxExpenseBenefits100.0100.0100.0100.0100.0100.0100.0

synh:IncreaseDecreaseInAccountsReceivableContractWithCustomerAssetNetCurrentAndContractWithCustomerLiabilityCurrent

synh:IncreaseDecreaseInAccountsReceivableContractWithCustomerAssetNetCurrentAndContractWithCustomerLiabilityCurrent


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value39-30.997-0.77437-105.748531020642548-19.827-21.98890
Percentage of IncreaseDecreaseInAccountsReceivableContractWithCustomerAssetNetCurrentAndContractWithCustomerLiabilityCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

synh:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTaxPortionAttributableToParent1

synh:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTaxPortionAttributableToParent1


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value4.7085.9372.7175.219-1.131-10.735.5080.074-8.962
Percentage of OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTaxPortionAttributableToParent1100.0100.0100.0100.0100.0100.0100.0100.0100.0

synh:OtherSundryNonoperatingIncomeExpense

synh:OtherSundryNonoperatingIncomeExpense


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-1298000.01526000.01822000.0-979000.0-238000.01185000.01213000.0-1180000.0-582000.0-592000.03599000.0-1618000.0319000.0-673000.0-499000.0-425000.0-97000.0-80000.0
Percentage of OtherSundryNonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

synh:ProceedsFromInvestmentsInUnconsolidatedAffiliates

synh:ProceedsFromInvestmentsInUnconsolidatedAffiliates


Proceeds
Period End2021-06-302021-03-312020-06-302020-03-31
Value682000.0-1374000.0452000.06750000.0
Percentage of ProceedsFromInvestmentsInUnconsolidatedAffiliates100.0100.0100.0100.0

synh:RestructuringChargeIncludingOtherCosts

synh:RestructuringChargeIncludingOtherCosts


Restructuring
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value3.9667.2286.06.5238.1718.722.31311149.2198.59113206.74.01.93.32.91.46.0
Percentage of RestructuringChargeIncludingOtherCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

synh:RestructuringChargeIncludingOtherCosts us-gaap:ConsolidationItems

us-gaap:CorporateNonSegment


Restructuring
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value3.9667.2286.06.5238.1718.722.3841311149.146198.59113206.674.0291.927
Percentage of RestructuringChargeIncludingOtherCosts100.0100.0100.0100.0100.0100.0103.7100.0100.0100.099.4100.0100.0100.099.999.6100.7101.4

synh:RestructuringChargeIncludingOtherCosts1 us-gaap:RestructuringCostAndReserve, us-gaap:ValuationAllowancesAndReservesType

synh:RestructuringChargeIncludingOtherCosts1

us-gaap:EmployeeSeverance, us-gaap:BusinessRestructuringReserves


Restructuring
Period End2021-06-302021-03-31
Value2.1326.293
Percentage of RestructuringChargeIncludingOtherCosts1100.0100.0

us-gaap:OtherRestructuring, us-gaap:BusinessRestructuringReserves


Restructuring
Period End2021-06-302021-03-31
Value-0.0480.047
Percentage of RestructuringChargeIncludingOtherCosts1-2.30.7

synh:RestructuringChargeIncludingOtherCosts1 us-gaap:ValuationAllowancesAndReservesType

us-gaap:BusinessRestructuringReserves


Restructuring
Period End2021-06-302021-03-31
Value2.0846.34
Percentage of RestructuringChargeIncludingOtherCosts197.7100.7

synh:StockRepurchaseProgramSharesPurchasedValue us-gaap:StatementClassOfStock

synh:StockRepurchaseProgramSharesPurchasedValue

us-gaap:CommonStock


Stock
Period End2021-06-302021-05-312021-03-312021-02-282020-10-312020-09-302020-06-302020-03-312019-08-312019-06-302019-02-282019-01-312018-04-302018-03-31
Value403244448.122300.0327.045234.993213737
Percentage of StockRepurchaseProgramSharesPurchasedValue100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0

synh:TradeReceivablesSold

synh:TradeReceivablesSold


Trade
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-30
Value3830393541364848
Percentage of TradeReceivablesSold100.0100.0100.0100.0100.0100.0100.0100.0

synh:TransactionAndIntegrationRelatedCosts

synh:TransactionAndIntegrationRelatedCosts


Transaction
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value126.9553.3687.57726107.654163.0181825158423
Percentage of TransactionAndIntegrationRelatedCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

synh:TransactionAndIntegrationRelatedCosts us-gaap:ConsolidationItems

us-gaap:CorporateNonSegment


Transaction
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value126.9553.3687.57726107.654163.037181825
Percentage of TransactionAndIntegrationRelatedCosts100.0100.0100.0100.0100.4100.0100.0100.0101.299.8100.2100.0

us-gaap:BusinessCombinationConsiderationTransferred1 us-gaap:BusinessAcquisition

us-gaap:BusinessCombinationConsiderationTransferred1

synh:IllingworthResearch


Business
Period End2020-12-17
Value80
Percentage of BusinessCombinationConsiderationTransferred1100.0

synh:SynteractAcquisition


Business
Period End2020-12-09
Value384
Percentage of BusinessCombinationConsiderationTransferred10.0

us-gaap:BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationAsset1

us-gaap:BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationAsset1


Business
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value0.00.597-0.127-0.152-0.1524.095-17.831-0.371.665
Percentage of BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationAsset10.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1

us-gaap:BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1


Business
Period End2021-06-30
Value1800000.0
Percentage of BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1100.0

us-gaap:BusinessCombinationIntegrationRelatedCosts

us-gaap:BusinessCombinationIntegrationRelatedCosts


Business
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.3721.1430.7071.5490.9311.3940.9090.8472.6282.1074.4489.293
Percentage of BusinessCombinationIntegrationRelatedCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashAcquiredFromAcquisition us-gaap:BusinessAcquisition

us-gaap:CashAcquiredFromAcquisition

synh:IllingworthResearch


Cash
Period End2020-12-17
Value1.1
Percentage of CashAcquiredFromAcquisition100.0

synh:SynteractAcquisition


Cash
Period End2020-12-09
Value28
Percentage of CashAcquiredFromAcquisition0.0

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

us-gaap:ConcentrationRiskPercentage1

us-gaap:AccountsReceivable, us-gaap:CustomerConcentrationRisk


Concentration
Period End2021-03-312019-03-312018-03-31
Value10.00.120.13
Percentage of ConcentrationRiskPercentage1100.0100.0100.0

us-gaap:SalesRevenueNet, us-gaap:CustomerConcentrationRisk


Concentration
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value10.010.010.00.110.0
Percentage of ConcentrationRiskPercentage10.0100.00.00.00.0

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

country:US, us-gaap:SalesRevenueNet, us-gaap:GeographicConcentrationRisk


Concentration
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value56.457.460.00.6010.6130.6330.6350.6290.6440.6440.6590.6260.542
Percentage of ConcentrationRiskPercentage10.0574.00.00.00.00.00.0524.20.00.0506.90.00.0

us-gaap:ContractWithCustomerLiabilityRevenueRecognized

us-gaap:ContractWithCustomerLiabilityRevenueRecognized


Contract
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302019-12-312019-09-302019-06-302018-09-302018-06-30
Value3933491329830111340367363207
Percentage of ContractWithCustomerLiabilityRevenueRecognized100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod

us-gaap:ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod


Contract
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302019-12-312019-09-302019-06-30
Value5.82641324.9261934
Percentage of ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DebtInstrumentBasisSpreadOnVariableRate1 us-gaap:ConsolidatedEntities, us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:VariableRate

us-gaap:DebtInstrumentBasisSpreadOnVariableRate1

srt:Subsidiaries, synh:AccountsReceivableSecuritization, synh:AccountsReceivableFinancingAgreementDueOctober2022, us-gaap:SecuredDebt, synh:FederalFundsRate


Debt
Period End2021-03-31
Value0.5
Percentage of DebtInstrumentBasisSpreadOnVariableRate1100.0

us-gaap:DebtInstrumentPeriodicPaymentPrincipal us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:DebtInstrumentPeriodicPaymentPrincipal

synh:A2017CreditAgreementAmendmentNo2TermLoanADueMarch2024, us-gaap:SecuredDebt


Debt
Period End2020-12-312020-09-30
Value0.019
Percentage of DebtInstrumentPeriodicPaymentPrincipal0.0100.0

us-gaap:Depreciation

us-gaap:Depreciation


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value181818171717181819191817171818146.0666.1646.0965.3055.064.8924.5974.3574.424.7664.9914.7345.0256.869
Percentage of Depreciation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DepreciationAmortizationAndAccretionNet us-gaap:ConsolidationItems

us-gaap:DepreciationAmortizationAndAccretionNet

us-gaap:CorporateNonSegment


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value575754555656606060617068676883651515
Percentage of DepreciationAmortizationAndAccretionNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EarlyRepaymentOfSeniorDebt

us-gaap:EarlyRepaymentOfSeniorDebt


Early
Period End2021-01-28
Value65
Percentage of EarlyRepaymentOfSeniorDebt100.0

us-gaap:EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents


Effect
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-1305000.0-3425000.01242000.02350000.05638000.0-420000.0-12690000.0305000.0-4287000.03078000.0-6809000.03309000.0-6278000.05127000.0233000.04195000.01834000.02854000.0
Percentage of EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings


Fair
Period End2021-06-302021-03-312020-12-31
Value-0.013-0.5970.152
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings100.0100.0100.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements


Fair
Period End2021-06-302021-03-312020-12-31
Value0.0-6.196-53.268
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements0.0100.0100.0

us-gaap:FairValueOfAssetsAcquired

us-gaap:FairValueOfAssetsAcquired


Fair
Period End2020-12-312020-06-30
Value0.027
Percentage of FairValueOfAssetsAcquired0.0100.0

us-gaap:FinitelivedIntangibleAssetsAcquired1 us-gaap:BusinessAcquisition

us-gaap:FinitelivedIntangibleAssetsAcquired1

synh:SynteractAcquisition


Finitelived
Period End2020-12-09
Value56
Percentage of FinitelivedIntangibleAssetsAcquired1100.0

us-gaap:FinitelivedIntangibleAssetsAcquired1 us-gaap:BusinessAcquisition, us-gaap:FiniteLivedIntangibleAssetsByMajorClass

synh:SynteractAcquisition, us-gaap:OrderOrProductionBacklog


Finitelived
Period End2020-12-09
Value37
Percentage of FinitelivedIntangibleAssetsAcquired166.0

synh:SynteractAcquisition, us-gaap:TradeNames


Finitelived
Period End2020-12-09
Value19
Percentage of FinitelivedIntangibleAssetsAcquired134.0

us-gaap:ForeignCurrencyTransactionGainLossBeforeTax

us-gaap:ForeignCurrencyTransactionGainLossBeforeTax


Foreign
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-5.9599.522-11.895-4.794-2.47815-17.2565.1330.880.0771.238-4.70625-6.364-1.648-0.382-3.175-2.707-1.892-5.196-5.819-7.774-1.507-2.1612.0742.389-3.3075.7562.6132.328
Percentage of ForeignCurrencyTransactionGainLossBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ForeignCurrencyTransactionGainLossRealized

us-gaap:ForeignCurrencyTransactionGainLossRealized


Foreign
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-0.57-1.192-0.403-4.823-3.045-5.096-37.484267.275-8.4068.3061.9785.685-5.517-1.535-5.147-3.482-0.673.9182.9782.5922.871.1381.092-0.7850.7924.76-0.544-3.002-1.09
Percentage of ForeignCurrencyTransactionGainLossRealized100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ForeignCurrencyTransactionGainLossRealized us-gaap:DerivativeInstrumentRisk

us-gaap:ForeignExchangeForward


Foreign
Period End2021-06-302021-03-31
Value0.41.1
Percentage of ForeignCurrencyTransactionGainLossRealized-70.2-92.3

us-gaap:ForeignCurrencyTransactionGainLossUnrealized

us-gaap:ForeignCurrencyTransactionGainLossUnrealized


Foreign
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-5.9599.522-11.894-4.794-2.478-15.019-17.2565.1310.880.0771.238-4.70625-6.364-1.648-0.381-3.175-2.707-1.892-5.196-5.82-7.774-1.507-2.1612.0742.389-3.3075.7562.6132.328
Percentage of ForeignCurrencyTransactionGainLossUnrealized100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:GainLossOnSaleOfBusiness us-gaap:StatementBusinessSegments

us-gaap:GainLossOnSaleOfBusiness

synh:ClinicalSolutionsSegment


Gain
Period End2020-12-31
Value7100000.0
Percentage of GainLossOnSaleOfBusiness100.0

us-gaap:GoodwillForeignCurrencyTranslationGainLoss

us-gaap:GoodwillForeignCurrencyTranslationGainLoss


Goodwill
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-31
Value3.9791.522-28.658-20.1250.20726-27.105148.139-11.585112.928-17.887-10.8813.6510.0870.5690.211-0.4030.21
Percentage of GoodwillForeignCurrencyTranslationGainLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:GoodwillForeignCurrencyTranslationGainLoss us-gaap:StatementBusinessSegments

synh:ClinicalSolutionsSegment


Goodwill
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value3.34649-19.622-13.6150.27620-20.144107.407-8.6169.3882.68722-11.927
Percentage of GoodwillForeignCurrencyTranslationGainLoss84.13224.668.567.7133.375.074.372.491.074.484.892.777.566.7

synh:CommercialSolutionsSegment


Goodwill
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.633-47.557-9.036-6.51-0.0696.747-6.9613.9220.732-2.9691.6850.2136.444-5.96
Percentage of GoodwillForeignCurrencyTranslationGainLoss15.9-3124.631.532.3-33.325.025.727.69.025.615.27.322.533.3

us-gaap:GoodwillPurchaseAccountingAdjustments

us-gaap:GoodwillPurchaseAccountingAdjustments


Goodwill
Period End2021-06-302021-03-312019-12-312019-09-302018-12-312018-09-302018-06-302018-03-31
Value5.6262.4791.0920.046-8.59380-2.125-4.214
Percentage of GoodwillPurchaseAccountingAdjustments100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:GoodwillPurchaseAccountingAdjustments us-gaap:StatementBusinessSegments

synh:ClinicalSolutionsSegment


Goodwill
Period End2021-06-302021-03-312019-12-312019-09-302018-12-312018-09-302018-06-302018-03-31
Value5.6262.4791.0920.00.0-1.884-1.279-2.529
Percentage of GoodwillPurchaseAccountingAdjustments100.0100.0100.00.0-0.0-2.360.260.0

us-gaap:GoodwillTransfers us-gaap:StatementBusinessSegments

us-gaap:GoodwillTransfers

synh:ClinicalSolutionsSegment


Goodwill
Period End2021-06-302021-03-31
Value0.044
Percentage of GoodwillTransfers0.0100.0

us-gaap:IncomeLossFromEquityMethodInvestments

us-gaap:IncomeLossFromEquityMethodInvestments


Income
Period End2021-06-30
Value-2800000.0
Percentage of IncomeLossFromEquityMethodInvestments100.0

us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities

us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value290.518-0.335621.669-66.42615-19.66858-26.682548.6410-14.241-6.85-18.82629-20.4577.552-4.964-8.97813108.1263.867-14.0787.1971.57627-10.705
Percentage of IncreaseDecreaseInAccountsPayableAndAccruedLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements


Incremental
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value1082000.01183000.061000.01311000.01021000.01377000.059000.01427000.01119000.001287000.001106000.00001184000.01108000.0-110000.01381000.01780000.01907000.015000.02439000.02233000.01859000.0-315000.0609000.0287000.00
Percentage of IncrementalCommonSharesAttributableToShareBasedPaymentArrangements100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.00.0100.00.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:InterestAndOtherIncome

us-gaap:InterestAndOtherIncome


Interest
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value071000.0122000.0336000.01481000.02426000.02133000.01502000.0188000.01004000.01655000.0839000.0417000.0501000.0152000.0112000.077000.062000.043000.034000.035000.028000.045000.084000.023000.026000.018000.0182000.0
Percentage of InterestAndOtherIncome0.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LineOfCreditFacilityDecreaseForgiveness1

us-gaap:LineOfCreditFacilityDecreaseForgiveness1


Line
Period End2021-01-28
Value65
Percentage of LineOfCreditFacilityDecreaseForgiveness1100.0

us-gaap:LineOfCreditFacilityDecreaseForgiveness1 us-gaap:DebtInstrument

synh:AccountsReceivableFinancingAgreementDueOctober2022


Line
Period End2021-01-28
Value65
Percentage of LineOfCreditFacilityDecreaseForgiveness1100.0

us-gaap:NoncashOrPartNoncashDivestitureAmountOfConsiderationReceived1 us-gaap:StatementBusinessSegments

us-gaap:NoncashOrPartNoncashDivestitureAmountOfConsiderationReceived1

synh:ClinicalSolutionsSegment


Noncash
Period End2020-12-31
Value5000000.0
Percentage of NoncashOrPartNoncashDivestitureAmountOfConsiderationReceived1100.0

us-gaap:OciBeforeReclassificationsBeforeTaxAttributableToParent us-gaap:StatementEquityComponents

us-gaap:OciBeforeReclassificationsBeforeTaxAttributableToParent

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Oci
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value-654000.01034000.0-510000.0-478000.0-6876000.0-19783000.01454000.0-1144000.0-9800000.0
Percentage of OciBeforeReclassificationsBeforeTaxAttributableToParent100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OciBeforeReclassificationsNetOfTaxAttributableToParent

us-gaap:OciBeforeReclassificationsNetOfTaxAttributableToParent


Oci
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-0.4880.772-2.4760.001-5.461-12.513.822-1.105-21.46316-34.0131.102-70.565343.2814.6467.3220
Percentage of OciBeforeReclassificationsNetOfTaxAttributableToParent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OciBeforeReclassificationsNetOfTaxAttributableToParent us-gaap:StatementEquityComponents

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Oci
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value8.8250.772-2.4760.001-5.461-12.513.822-1.105-9.544
Percentage of OciBeforeReclassificationsNetOfTaxAttributableToParent-1808.4100.0100.0100.0100.0100.0100.0100.044.5

us-gaap:AccumulatedTranslationAdjustment


Oci
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-0.488-4.3146332.87-48.78849-34.421-11.91920-24.494-1.295-69.169332.8844.6267.48619-6.8610.981
Percentage of OciBeforeReclassificationsNetOfTaxAttributableToParent100.0-558.3-1890.33383200.0-52.6390.01306.53115.055.5122.172.0-117.598.097.987.999.6102.397.80.00.0

us-gaap:OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent

us-gaap:OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value8.825-4.3146332.87-48.78849-34.421-11.91920-24.494-1.295-69.169332.8844.6267.4864.846-6.8610.981-1.269
Percentage of OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value8.825-4.3146332.87-48.78849-34.421-11.91920-24.494-1.295-69.169
Percentage of OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsTax

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsTax


Other
Period End2021-06-302021-03-312020-06-302020-03-31
Value-0.1660.262-1.415-7.273
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsTax100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value-1.9660.4791.4157.273-2.368-0.039-0.256
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsTax0.00.0-100.0-100.00.00.00.0

us-gaap:AccumulatedTranslationAdjustment


Other
Period End2021-06-302021-03-312020-06-302020-03-31
Value9.375-5.0182.87-48.788
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsTax-5647.6-1915.3-202.8670.8

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value-1596000.0-2013000.0-6597000.0-1384000.0-52000.06639000.0-1790000.00-237000.0
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax100.0100.0100.0100.0100.0100.0100.00.0100.0

us-gaap:OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax

us-gaap:OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-550000.0-708000.01354000.000000000-2868000.002868000.03132000.05873000.00000
Percentage of OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax100.0100.0100.00.00.00.00.00.00.00.00.0100.00.0100.0100.0100.00.00.00.00.0

us-gaap:OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Other
Period End2021-06-302021-03-31
Value550000.0-708000.0
Percentage of OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax-100.0100.0

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value131.62749391.739-59.51855-34.347-20.88116-34.461.329-70.886343.1554.5117.2034.996
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent us-gaap:StatementEquityComponents

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value4.7085.9372.7175.219-1.131-10.735.5080.074-8.962
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent34.8364.95.513.4-65.018.09.9-0.242.9

us-gaap:AccumulatedTranslationAdjustment


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value8.825-4.31332.87-48.78849-34.421-11.91920-24.494-1.295-69.169332.8844.6267.4864.846-6.8610.981
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent65.2-264.986.6165.082.090.1100.257.1125.771.1-97.497.698.791.4102.5103.997.00.00.0

us-gaap:OtherNoncashIncomeExpense

us-gaap:OtherNoncashIncomeExpense


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-4054000.0-953000.0116000.0-380000.0-397000.0-1104000.0-1589000.0-30000.0-1621000.0474000.0235000.0972000.0-2260000.0-1796000.0-3308000.0-704000.0-336000.0-364000.0-126000.0-23000.0-7000.0-130000.0-70000.0-11000.047000.0116000.01241000.0-157000.0-222000.0-9000.0
Percentage of OtherNoncashIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentForContingentConsiderationLiabilityFinancingActivities

us-gaap:PaymentForContingentConsiderationLiabilityFinancingActivities


Payment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.06.1960.00.00.042260.00.170.00.008230.00.00.0
Percentage of PaymentForContingentConsiderationLiabilityFinancingActivities0.0100.00.00.0100.0100.00.0100.00.0100.0100.00.00.00.0

us-gaap:PaymentsOfDebtIssuanceCosts

us-gaap:PaymentsOfDebtIssuanceCosts


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312016-09-302015-12-312015-09-302014-12-312014-09-30
Value0.4950.0499.270.30.00.00.0431.5610.8480.1840.0-0.3593.4210.00.0250.00.8680.00.05.3640.0
Percentage of PaymentsOfDebtIssuanceCosts100.0100.0100.0100.00.00.0100.0100.0100.0100.00.0100.0100.00.00.0100.00.0100.00.00.0100.00.0

us-gaap:PaymentsRelatedToTaxWithholdingForShareBasedCompensation

us-gaap:PaymentsRelatedToTaxWithholdingForShareBasedCompensation


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-30
Value3.597260.5191.0970.459190.6320.740.224110.1470.8290.062.3231.4334.2120.0061.1730.0140.7880.0260.0110.0332.5170.6440.00.00.0
Percentage of PaymentsRelatedToTaxWithholdingForShareBasedCompensation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.0

us-gaap:PaymentsToAcquireBusinessesNetOfCashAcquired

us-gaap:PaymentsToAcquireBusinessesNetOfCashAcquired


Payments
Period End2021-06-302021-03-312019-12-312018-12-312017-12-312016-12-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value4.6539.9820.7120.00.00.00.00.00.00.00.00.00.02.302
Percentage of PaymentsToAcquireBusinessesNetOfCashAcquired100.0100.0100.00.00.00.00.00.00.00.00.00.00.0100.0

us-gaap:PaymentsToAcquireBusinessesNetOfCashAcquired us-gaap:BusinessAcquisition

synh:IllingworthResearch


Payments
Period End2021-03-31
Value9.0
Percentage of PaymentsToAcquireBusinessesNetOfCashAcquired90.2

synh:SynteractAcquisition


Payments
Period End2021-03-31
Value1.0
Percentage of PaymentsToAcquireBusinessesNetOfCashAcquired10.0

us-gaap:PaymentsToAcquireBusinessesNetOfCashAcquired us-gaap:BusinessAcquisition, us-gaap:SubsequentEventType

synh:IllingworthResearch, us-gaap:SubsequentEvent


Payments
Period End2021-01-31
Value8.4
Percentage of PaymentsToAcquireBusinessesNetOfCashAcquired0.0

us-gaap:PaymentsToAcquireInterestInSubsidiariesAndAffiliates

us-gaap:PaymentsToAcquireInterestInSubsidiariesAndAffiliates


Payments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-09-30
Value8.73-0.3430.4526.757.7496.2273.00.00.0
Percentage of PaymentsToAcquireInterestInSubsidiariesAndAffiliates100.0100.0100.0100.0100.0100.0100.00.00.0

us-gaap:ProceedsFromAccountsReceivableSecuritization

us-gaap:ProceedsFromAccountsReceivableSecuritization


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value0.0650.0250.06.6-0.1858911264.11830.00.00.0
Percentage of ProceedsFromAccountsReceivableSecuritization0.0100.00.0100.00.0100.0100.0100.0100.0100.0100.0100.00.00.00.0

us-gaap:ProceedsFromDivestitureOfBusinesses

us-gaap:ProceedsFromDivestitureOfBusinesses


Proceeds
Period End2020-12-31
Value18
Percentage of ProceedsFromDivestitureOfBusinesses100.0

us-gaap:ProceedsFromDivestitureOfBusinesses us-gaap:StatementBusinessSegments

synh:ClinicalSolutionsSegment


Proceeds
Period End2020-12-31
Value18
Percentage of ProceedsFromDivestitureOfBusinesses100.0

us-gaap:ProceedsFromLinesOfCredit

us-gaap:ProceedsFromLinesOfCredit


Proceeds
Period End2020-12-312020-09-302020-06-302020-03-312019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-30
Value0.00.00.03000.00.00.00.00.00.00.00.00.0150.085150.0450.0
Percentage of ProceedsFromLinesOfCredit0.00.00.0100.00.00.00.00.00.00.00.00.00.0100.00.0100.0100.00.0100.00.0

us-gaap:ProceedsFromSaleAndCollectionOfReceivables

us-gaap:ProceedsFromSaleAndCollectionOfReceivables


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value3830393541364848397354955545
Percentage of ProceedsFromSaleAndCollectionOfReceivables100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromSaleOfNotesReceivable us-gaap:StatementBusinessSegments

us-gaap:ProceedsFromSaleOfNotesReceivable

synh:ClinicalSolutionsSegment


Proceeds
Period End2021-06-30
Value5000000.0
Percentage of ProceedsFromSaleOfNotesReceivable100.0

us-gaap:ProceedsFromStockOptionsExercised

us-gaap:ProceedsFromStockOptionsExercised


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-30
Value3.678101.595100.426120.647154.653193.779101.795.6682.287101.0985.1533.4765.295.5663.5592.5981.0580.00.00.0370.096
Percentage of ProceedsFromStockOptionsExercised100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.0

us-gaap:ProfessionalFees

us-gaap:ProfessionalFees


Professional
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value115.6562.438107.9067.1086.6781215141114
Percentage of ProfessionalFees100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProvisionForDoubtfulAccounts

us-gaap:ProvisionForDoubtfulAccounts


Provision
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-286000.0-187000.0-662000.0978000.0108000.0271000.0949000.0165000.0-519000.01302000.0-1134000.0-1719000.0-1905000.0171000.02690000.01319000.0165000.0-7000.0643000.0829000.0-31000.01129000.0296000.0-295000.0-356000.0211000.0-376000.01275000.0970000.0566000.0
Percentage of ProvisionForDoubtfulAccounts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent us-gaap:StatementEquityComponents

us-gaap:ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Reclassification
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value-6.958-6.91637-7.081-5.797-2.414-2.264-1.218-0.601
Percentage of ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent us-gaap:StatementEquityComponents

us-gaap:ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Reclassification
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value-5196000.0-5165000.0-5193000.0-5218000.0-4330000.0-1780000.0-1686000.0-1179000.0-582000.0
Percentage of ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ReclassificationFromAociCurrentPeriodTax us-gaap:StatementEquityComponents

us-gaap:ReclassificationFromAociCurrentPeriodTax

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Reclassification
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value1762000.01751000.0-9771000.01863000.01467000.0634000.0-578000.0-39000.0-19000.0
Percentage of ReclassificationFromAociCurrentPeriodTax100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty

us-gaap:RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty


Related
Period End2021-06-30
Value700000.0
Percentage of RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty100.0

us-gaap:RelatedPartyTransactionPurchasesFromRelatedParty us-gaap:TitleOfIndividual

us-gaap:RelatedPartyTransactionPurchasesFromRelatedParty

srt:Director


Related
Period End2021-06-302021-03-31
Value1300000.0300000.0
Percentage of RelatedPartyTransactionPurchasesFromRelatedParty100.0100.0

us-gaap:RepaymentsOfAccountsReceivableSecuritization

us-gaap:RepaymentsOfAccountsReceivableSecuritization


Repayments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value0.00.00.06.60.00.0220.0180.0
Percentage of RepaymentsOfAccountsReceivableSecuritization0.00.00.0100.00.00.0100.00.0100.00.0

us-gaap:RepaymentsOfLinesOfCredit

us-gaap:RepaymentsOfLinesOfCredit


Repayments
Period End2020-12-312020-09-302018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value0.01500.00.00.00.00.00.015250.0601530150.00.00.0
Percentage of RepaymentsOfLinesOfCredit0.0100.00.00.00.00.00.00.0100.0100.00.0100.0100.0100.0100.00.00.00.0

us-gaap:RepaymentsOfLongTermCapitalLeaseObligations

us-gaap:RepaymentsOfLongTermCapitalLeaseObligations


Repayments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value4.1114.2693.6993.8314.234.6745.0644.7522.7593.8014.3844.4794.5593.5860.00.00.00.00.00.00.0540.0570.1420.1990.2250.8420.80.813
Percentage of RepaymentsOfLongTermCapitalLeaseObligations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RestructuringAndRelatedCostIncurredCost

us-gaap:RestructuringAndRelatedCostIncurredCost


Restructuring
Period End2021-06-302021-03-312020-06-302020-03-31
Value3.9667.2288.1718.72
Percentage of RestructuringAndRelatedCostIncurredCost100.0100.0100.0100.0

us-gaap:RestructuringAndRelatedCostIncurredCost us-gaap:BusinessAcquisition, us-gaap:RestructuringCostAndReserve

synh:InVentivMerger, us-gaap:EmployeeSeverance


Restructuring
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.00.01.0-2.5712.45.96.34.8211.92.98.4
Percentage of RestructuringAndRelatedCostIncurredCost0.00.011.50.00.00.00.00.00.00.00.0

synh:InVentivMerger, us-gaap:FacilityClosing


Restructuring
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.40.20.62.242.36.42.03.49152.62.2
Percentage of RestructuringAndRelatedCostIncurredCost0.02.46.90.00.00.00.00.00.00.00.0

us-gaap:RestructuringAndRelatedCostIncurredCost us-gaap:RestructuringCostAndReserve

us-gaap:EmployeeSeverance


Restructuring
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value2.0846.2935.175.97.6476.62.1145.8-0.76.00.2220.70.80.2
Percentage of RestructuringAndRelatedCostIncurredCost52.587.10.00.093.675.70.00.00.00.00.00.00.00.0

us-gaap:FacilityClosing


Restructuring
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value1.8820.8880.180.10.3750.1-0.1383.10.10.20.1670.00.60.8
Percentage of RestructuringAndRelatedCostIncurredCost47.512.30.00.04.61.10.00.00.00.00.00.00.00.0

us-gaap:OtherRestructuring


Restructuring
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312018-12-312018-09-302018-06-302018-03-31
Value0.00.0470.180.10.1490.40.1450.20.70.1
Percentage of RestructuringAndRelatedCostIncurredCost0.00.70.00.01.84.60.00.00.00.0

us-gaap:RevenueFromRelatedParties

us-gaap:RevenueFromRelatedParties


Revenue
Period End2021-06-302021-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-30
Value1200000.0300000.0300000.0100000.0200000.0100000.0000
Percentage of RevenueFromRelatedParties100.0100.0100.0100.0100.0100.00.00.00.0

us-gaap:StockRepurchasedDuringPeriodValue us-gaap:StatementClassOfStock

us-gaap:StockRepurchasedDuringPeriodValue

us-gaap:CommonClassA


Stock
Period End2021-06-302021-03-312020-09-302015-12-312015-05-31
Value734430135150
Percentage of StockRepurchasedDuringPeriodValue100.0100.0100.0100.0100.0

us-gaap:StockRepurchasedDuringPeriodValue us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Stock
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value29194.983160.0190.04.64816220.00.03330
Percentage of StockRepurchasedDuringPeriodValue40.844.50.056.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stock
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.0090.0060.0020.0050.00.0060.00.0010.0050.0070.00.00.010.009
Percentage of StockRepurchasedDuringPeriodValue0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stock
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value43243.137130.0120.02.3966.3154.4770.00.03.9826.501
Percentage of StockRepurchasedDuringPeriodValue59.255.50.044.00.00.00.00.00.00.00.00.00.00.0

us-gaap:TreasuryStockAcquiredAverageCostPerShare us-gaap:StatementClassOfStock

us-gaap:TreasuryStockAcquiredAverageCostPerShare

us-gaap:CommonStock


Treasury
Period End2021-06-302021-05-312021-03-312021-02-282020-10-312020-09-302020-03-312019-08-312019-06-302019-02-282019-01-312018-04-302018-03-31
Value81.281.0474.1874.1854.1459.2653.3849.9345.2941.439.1636.639.55
Percentage of TreasuryStockAcquiredAverageCostPerShare100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:UnrecognizedTaxBenefitsPeriodIncreaseDecrease us-gaap:IncomeTaxAuthority

us-gaap:UnrecognizedTaxBenefitsPeriodIncreaseDecrease

us-gaap:ForeignCountry


Unrecognized
Period End2021-06-302021-03-31
Value100000.0500000.0
Percentage of UnrecognizedTaxBenefitsPeriodIncreaseDecrease100.0100.0

us-gaap:UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations

us-gaap:UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations


Unrecognized
Period End2021-06-302021-03-31
Value-0.60.6
Percentage of UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations100.0100.0

us-gaap:ValuationAllowancesAndReservesChargedToCostAndExpense us-gaap:RestructuringCostAndReserve, us-gaap:ValuationAllowancesAndReservesType

us-gaap:ValuationAllowancesAndReservesChargedToCostAndExpense

us-gaap:EmployeeSeverance, us-gaap:BusinessRestructuringReserves


Valuation
Period End2020-09-30
Value5.904
Percentage of ValuationAllowancesAndReservesChargedToCostAndExpense100.0

us-gaap:OtherRestructuring, us-gaap:BusinessRestructuringReserves


Valuation
Period End2020-09-302017-09-302017-06-302017-03-31
Value0.1220.8370.5740.527
Percentage of ValuationAllowancesAndReservesChargedToCostAndExpense2.10.00.00.0

us-gaap:ValuationAllowancesAndReservesChargedToCostAndExpense us-gaap:ValuationAllowancesAndReservesType

us-gaap:BusinessRestructuringReserves


Valuation
Period End2020-09-302017-09-302017-06-302017-03-31
Value6.0265.8213.7041.601
Percentage of ValuationAllowancesAndReservesChargedToCostAndExpense102.10.00.00.0

us-gaap:ValuationAllowancesAndReservesDeductions us-gaap:RestructuringCostAndReserve, us-gaap:ValuationAllowancesAndReservesType

us-gaap:ValuationAllowancesAndReservesDeductions

us-gaap:EmployeeSeverance, us-gaap:BusinessRestructuringReserves


Valuation
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-30
Value2.1628.716-7.296-23.9839.0342.454
Percentage of ValuationAllowancesAndReservesDeductions100.0100.0100.0100.0100.0100.0

us-gaap:OtherRestructuring, us-gaap:BusinessRestructuringReserves


Valuation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-0.0480.0471.43-0.122-0.8610.3660.4170.2330.0320.0380.4930.9291.9821.6833.440.8260.5290.562
Percentage of ValuationAllowancesAndReservesDeductions-2.20.50.01.73.64.10.09.50.00.00.00.00.00.00.00.00.00.0

us-gaap:ValuationAllowancesAndReservesDeductions us-gaap:ValuationAllowancesAndReservesType

us-gaap:BusinessRestructuringReserves


Valuation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value2.1148.76349-7.418-24.8449.44.8932.687164.109116.4028.8112128.0293.0783.194
Percentage of ValuationAllowancesAndReservesDeductions97.8100.50.0101.7103.6104.10.0109.50.00.00.00.00.00.00.00.00.00.0

synh:AccruedRebatesToCustomersCurrent

synh:AccruedRebatesToCustomersCurrent


Accrued
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value2225232713
Percentage of AccruedRebatesToCustomersCurrent100.0100.0100.0100.0100.0

synh:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccountsPayableAndAccruedExpenses us-gaap:BusinessAcquisition

synh:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccountsPayableAndAccruedExpenses

synh:SynteractAcquisition


Business
Period End2020-12-09
Value27
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccountsPayableAndAccruedExpenses100.0

synh:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedContractWithCustomerLiability us-gaap:BusinessAcquisition

synh:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedContractWithCustomerLiability

synh:SynteractAcquisition


Business
Period End2020-12-09
Value46
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedContractWithCustomerLiability100.0

synh:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsAccountsReceivableAndUnbilledServices us-gaap:BusinessAcquisition

synh:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsAccountsReceivableAndUnbilledServices

synh:SynteractAcquisition


Business
Period End2020-12-09
Value49
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsAccountsReceivableAndUnbilledServices100.0

synh:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightOfUseAssets us-gaap:BusinessAcquisition

synh:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightOfUseAssets

synh:SynteractAcquisition


Business
Period End2020-12-09
Value10
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightOfUseAssets100.0

synh:BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedCurrentTaxSharingObligation

synh:BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedCurrentTaxSharingObligation


Business
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value4.3272611220.0
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedCurrentTaxSharingObligation100.0100.0100.0100.00.0

synh:CashandCashEquivalentsCashPoolingAgreementCashPoolBorrowings

synh:CashandCashEquivalentsCashPoolingAgreementCashPoolBorrowings


Cashand
Period End2021-06-302021-03-312020-12-312019-12-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value2051782043071991059712888
Percentage of CashandCashEquivalentsCashPoolingAgreementCashPoolBorrowings100.0100.0100.0100.0100.0100.0100.0100.0100.0

synh:CashandCashEquivalentsCashPoolingAgreementGrossCashPosition

synh:CashandCashEquivalentsCashPoolingAgreementGrossCashPosition


Cashand
Period End2021-06-302021-03-312020-12-312019-12-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value232193220326206130131145195
Percentage of CashandCashEquivalentsCashPoolingAgreementGrossCashPosition100.0100.0100.0100.0100.0100.0100.0100.0100.0

synh:CashandCashEquivalentsCashPoolingAgreementNetCashPosition

synh:CashandCashEquivalentsCashPoolingAgreementNetCashPosition


Cashand
Period End2021-06-302021-03-312020-12-312019-12-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value261415186.931243416107
Percentage of CashandCashEquivalentsCashPoolingAgreementNetCashPosition100.0100.0100.0100.0100.0100.0100.0100.0100.0

synh:ContractualObligationNotYetSatisfied

synh:ContractualObligationNotYetSatisfied


Contractual
Period End2021-06-302021-03-312020-12-312020-09-30
Value14131414
Percentage of ContractualObligationNotYetSatisfied100.0100.0100.0100.0

synh:DeferredTaxAssetInterestLimitationCarryforward

synh:DeferredTaxAssetInterestLimitationCarryforward


Deferred
Period End2020-12-312019-12-312018-12-312017-12-31
Value2015120.0
Percentage of DeferredTaxAssetInterestLimitationCarryforward100.0100.0100.00.0

synh:DeferredTaxAssetsTaxDeferredExpenseLeaseObligations

synh:DeferredTaxAssetsTaxDeferredExpenseLeaseObligations


Deferred
Period End2020-12-312019-12-312018-12-31
Value57640.0
Percentage of DeferredTaxAssetsTaxDeferredExpenseLeaseObligations100.0100.00.0

synh:DeferredTaxAssetsTaxDeferredExpensePrepaidRoyalty

synh:DeferredTaxAssetsTaxDeferredExpensePrepaidRoyalty


Deferred
Period End2020-12-312019-12-312018-12-31
Value3451000.06525000.00
Percentage of DeferredTaxAssetsTaxDeferredExpensePrepaidRoyalty100.0100.00.0

synh:DeferredTaxLiabilitiesRightOfUseAssets

synh:DeferredTaxLiabilitiesRightOfUseAssets


Deferred
Period End2020-12-312019-12-312018-12-31
Value49570.0
Percentage of DeferredTaxLiabilitiesRightOfUseAssets100.0100.00.0

synh:FinanceLeaseLiabilityManagementFee

synh:FinanceLeaseLiabilityManagementFee


Finance
Period End2020-12-31
Value680000.0
Percentage of FinanceLeaseLiabilityManagementFee100.0

synh:FinanceLeaseRightOfUseAssetAccumulatedDepreciation

synh:FinanceLeaseRightOfUseAssetAccumulatedDepreciation


Finance
Period End2020-12-312019-12-31
Value2020
Percentage of FinanceLeaseRightOfUseAssetAccumulatedDepreciation100.0100.0

synh:ForeignEarningsPreviouslyTaxedintheUSIntendedToBePermanentlyReinvested

synh:ForeignEarningsPreviouslyTaxedintheUSIntendedToBePermanentlyReinvested


Foreign
Period End2020-12-31
Value324
Percentage of ForeignEarningsPreviouslyTaxedintheUSIntendedToBePermanentlyReinvested100.0

synh:ForeignEarningsPreviouslyTaxedintheUSIntendedToBeRepatriated

synh:ForeignEarningsPreviouslyTaxedintheUSIntendedToBeRepatriated


Foreign
Period End2020-12-31
Value388
Percentage of ForeignEarningsPreviouslyTaxedintheUSIntendedToBeRepatriated100.0

synh:ForeignEarningsPreviouslyTaxedintheUSTotal

synh:ForeignEarningsPreviouslyTaxedintheUSTotal


Foreign
Period End2020-12-31
Value712
Percentage of ForeignEarningsPreviouslyTaxedintheUSTotal100.0

synh:LongTermDebtMaturitiesRepaymentsOfInterestInYearFive

synh:LongTermDebtMaturitiesRepaymentsOfInterestInYearFive


Long
Period End2020-09-30
Value12
Percentage of LongTermDebtMaturitiesRepaymentsOfInterestInYearFive100.0

synh:LongTermDebtMaturitiesRepaymentsOfInterestInYearFour

synh:LongTermDebtMaturitiesRepaymentsOfInterestInYearFour


Long
Period End2020-09-30
Value36
Percentage of LongTermDebtMaturitiesRepaymentsOfInterestInYearFour100.0

synh:LongTermDebtMaturitiesRepaymentsOfInterestInYearThree

synh:LongTermDebtMaturitiesRepaymentsOfInterestInYearThree


Long
Period End2020-09-30
Value41
Percentage of LongTermDebtMaturitiesRepaymentsOfInterestInYearThree100.0

synh:LongTermDebtMaturitiesRepaymentsOfInterestInYearTwo

synh:LongTermDebtMaturitiesRepaymentsOfInterestInYearTwo


Long
Period End2020-09-30
Value45
Percentage of LongTermDebtMaturitiesRepaymentsOfInterestInYearTwo100.0

synh:LongTermDebtMaturitiesRepaymentsOfInterestRemainderOfFiscalYear

synh:LongTermDebtMaturitiesRepaymentsOfInterestRemainderOfFiscalYear


Long
Period End2020-09-30
Value11
Percentage of LongTermDebtMaturitiesRepaymentsOfInterestRemainderOfFiscalYear100.0

synh:LongTermDebtRepaymentsOfInterest

synh:LongTermDebtRepaymentsOfInterest


Long
Period End2020-09-30
Value147
Percentage of LongTermDebtRepaymentsOfInterest100.0

synh:OperatingAndFinanceLeaseLiabilityPaymentsDue

synh:OperatingAndFinanceLeaseLiabilityPaymentsDue


Operating
Period End2020-12-31
Value368
Percentage of OperatingAndFinanceLeaseLiabilityPaymentsDue100.0

synh:OperatingAndFinanceLeaseLiabilityPaymentsDueAfterYearFive

synh:OperatingAndFinanceLeaseLiabilityPaymentsDueAfterYearFive


Operating
Period End2020-12-31
Value99
Percentage of OperatingAndFinanceLeaseLiabilityPaymentsDueAfterYearFive100.0

synh:OperatingAndFinanceLeaseLiabilityPaymentsDueYearFive

synh:OperatingAndFinanceLeaseLiabilityPaymentsDueYearFive


Operating
Period End2020-12-31
Value29
Percentage of OperatingAndFinanceLeaseLiabilityPaymentsDueYearFive100.0

synh:OperatingAndFinanceLeaseLiabilityPaymentsDueYearFour

synh:OperatingAndFinanceLeaseLiabilityPaymentsDueYearFour


Operating
Period End2020-12-31
Value41
Percentage of OperatingAndFinanceLeaseLiabilityPaymentsDueYearFour100.0

synh:OperatingAndFinanceLeaseLiabilityPaymentsDueYearThree

synh:OperatingAndFinanceLeaseLiabilityPaymentsDueYearThree


Operating
Period End2020-12-31
Value56
Percentage of OperatingAndFinanceLeaseLiabilityPaymentsDueYearThree100.0

synh:OperatingAndFinanceLeaseLiabilityPaymentsDueYearTwo

synh:OperatingAndFinanceLeaseLiabilityPaymentsDueYearTwo


Operating
Period End2020-12-31
Value69
Percentage of OperatingAndFinanceLeaseLiabilityPaymentsDueYearTwo100.0

synh:OperatingAndFinanceLeaseLiabilityPaymentsNextTwelveMonths

synh:OperatingAndFinanceLeaseLiabilityPaymentsNextTwelveMonths


Operating
Period End2020-12-31
Value72
Percentage of OperatingAndFinanceLeaseLiabilityPaymentsNextTwelveMonths100.0

synh:PercentageOfCashAndCashEquivalentsBalanceConsolidated us-gaap:ConcentrationRiskByType, us-gaap:GeographicDistribution

synh:PercentageOfCashAndCashEquivalentsBalanceConsolidated

us-gaap:CustomerConcentrationRisk, us-gaap:GeographicDistributionForeign


Percentage
Period End2021-06-302020-12-31
Value56.019.0
Percentage of PercentageOfCashAndCashEquivalentsBalanceConsolidated100.0100.0

synh:PercentageOfOutstandingSharesPurchase us-gaap:BusinessAcquisition

synh:PercentageOfOutstandingSharesPurchase

synh:SynteractAcquisition


Percentage
Period End2020-12-09
Value100.0
Percentage of PercentageOfOutstandingSharesPurchase100.0

synh:PercentageOfOutstandingSharesPurchase us-gaap:SubsequentEventType

us-gaap:SubsequentEvent


Percentage
Period End2020-10-26
Value100.0
Percentage of PercentageOfOutstandingSharesPurchase0.0

synh:ReceivablesNetCurrentAndContractWithCustomerAssetNetCurrent

synh:ReceivablesNetCurrentAndContractWithCustomerAssetNetCurrent


Receivables
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value136912991344126411741340130312951287122112561015
Percentage of ReceivablesNetCurrentAndContractWithCustomerAssetNetCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

synh:StockholdersEquityAttributableToParentAdjustedBalance

synh:StockholdersEquityAttributableToParentAdjustedBalance


Stockholders
Period End2021-03-312020-12-312020-06-302020-03-312019-12-312019-06-302019-03-312018-12-312018-04-012017-12-312016-12-312015-12-31
Value3236302629992977285628232838292329072923299224
Percentage of StockholdersEquityAttributableToParentAdjustedBalance100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

synh:StockholdersEquityAttributableToParentAdjustedBalance us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2020-12-312019-12-312019-04-012018-12-312018-04-012017-12-312016-12-312015-12-31
Value-71.593-88.195-71.807-88.19515-18.535-42.25-41.543
Percentage of StockholdersEquityAttributableToParentAdjustedBalance-2.4-3.10.0-3.00.5-0.6-14.1-18.5

us-gaap:RetainedEarnings


Stockholders
Period End2021-03-312020-12-312020-06-302020-03-312019-12-312019-06-302019-03-312018-12-312018-04-012017-12-312017-01-012016-12-312015-12-31
Value-165.831-344.034-318.838-344.0343026-488.837-459.3332856-504.187-473.134-232.0-232.0-293.918
Percentage of StockholdersEquityAttributableToParentAdjustedBalance-5.1-11.4-10.6-11.6106.0-17.3-16.297.7-17.3-16.20.0-77.5-130.6

us-gaap:AccountsReceivableGrossCurrent

us-gaap:AccountsReceivableGrossCurrent


Accounts
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value768705774663659771787774781729733662689610652564229193217184195202161180147153133131
Percentage of AccountsReceivableGrossCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AccruedProfessionalFeesCurrent

us-gaap:AccruedProfessionalFeesCurrent


Accrued
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302016-12-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value23125223013284265.195.7234.4073.8326.6146.835
Percentage of AccruedProfessionalFeesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent


Allowance
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value7319000.07679000.07615000.08159000.07949000.07932000.05381000.04974000.05296000.05882000.04587000.05456000.07382000.09537000.09076000.07361000.06001000.05889000.05884000.05323000.04629000.04661000.03557000.03282000.03643000.04006000.03727000.01384000.0
Percentage of AllowanceForDoubtfulAccountsReceivableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AlternativeInvestment us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency, us-gaap:InvestmentType

us-gaap:AlternativeInvestment

us-gaap:FairValueMeasuredAtNetAssetValuePerShare, us-gaap:FairValueMeasurementsRecurring, srt:PartnershipInterest


Alternative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-30
Value9073000.08391000.08665000.07336000.07678000.07226000.07226000.06227000.0
Percentage of AlternativeInvestment100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AlternativeInvestment us-gaap:FairValueByMeasurementFrequency, us-gaap:InvestmentType

us-gaap:FairValueMeasurementsRecurring, srt:PartnershipInterest


Alternative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-30
Value9073000.08391000.08665000.07336000.07678000.07226000.07226000.06227000.0
Percentage of AlternativeInvestment100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AssetsFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:AssetsFairValueDisclosure

us-gaap:FairValueInputsLevel1, us-gaap:FairValueMeasurementsRecurring


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value24232220191821212120141716161615
Percentage of AssetsFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueMeasuredAtNetAssetValuePerShare, us-gaap:FairValueMeasurementsRecurring


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-30
Value9.0738.3918.6657.3367.6787.2267.2266.227
Percentage of AssetsFairValueDisclosure36.635.537.835.238.640.033.529.6

us-gaap:AssetsFairValueDisclosure us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsRecurring


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value33323128272528272121162219181817
Percentage of AssetsFairValueDisclosure136.6135.5137.8135.2138.6140.0134.2131.1102.5106.0112.0130.1115.7116.1113.4111.3

us-gaap:BusinessCombinationContingentConsiderationAsset us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:BusinessCombinationContingentConsiderationAsset

synh:RelatedParty


Business
Period End2021-06-30
Value1800000.0
Percentage of BusinessCombinationContingentConsiderationAsset100.0

us-gaap:BusinessCombinationContingentConsiderationAsset us-gaap:StatementBusinessSegments

synh:ClinicalSolutionsSegment


Business
Period End2020-12-31
Value3600000.0
Percentage of BusinessCombinationContingentConsiderationAsset0.0

us-gaap:BusinessCombinationContingentConsiderationLiability us-gaap:BusinessAcquisition, us-gaap:FairValueByMeasurementFrequency

us-gaap:BusinessCombinationContingentConsiderationLiability

synh:InVentivMerger, us-gaap:FairValueMeasurementsRecurring


Business
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value6.26.86.66.56.43214141615545250
Percentage of BusinessCombinationContingentConsiderationLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:BusinessCombinationContingentConsiderationLiability us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueInputsLevel3, us-gaap:FairValueMeasurementsRecurring


Business
Period End2021-06-302020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value0.9956.7936.6416.496.38371919202058525150
Percentage of BusinessCombinationContingentConsiderationLiability0.099.9100.699.899.7114.1128.9130.3127.8128.2108.299.90.0100.0

us-gaap:BusinessCombinationContingentConsiderationLiability us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsRecurring


Business
Period End2021-06-302020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value0.9956.7936.6416.496.38371919202058525150
Percentage of BusinessCombinationContingentConsiderationLiability0.099.9100.699.899.7114.1128.9130.3127.8128.2108.299.90.0100.0

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets us-gaap:BusinessAcquisition

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets

synh:SynteractAcquisition


Business
Period End2020-12-09
Value511
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets100.0

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligation us-gaap:BusinessAcquisition

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligation

synh:SynteractAcquisition


Business
Period End2020-12-09
Value15
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligation100.0

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents us-gaap:BusinessAcquisition

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents

synh:SynteractAcquisition


Business
Period End2020-12-09
Value28
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents100.0

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets us-gaap:BusinessAcquisition

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets

synh:SynteractAcquisition


Business
Period End2020-12-09
Value2912000.0
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets100.0

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities us-gaap:BusinessAcquisition

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities

synh:SynteractAcquisition


Business
Period End2020-12-09
Value7.762
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities100.0

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill us-gaap:BusinessAcquisition

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill

synh:IllingworthResearch


Business
Period End2020-12-17
Value21
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill100.0

synh:SynteractAcquisition


Business
Period End2020-12-09
Value56
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill0.0

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles us-gaap:BusinessAcquisition

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles

synh:SynteractAcquisition


Business
Period End2020-12-09
Value56
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles100.0

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities us-gaap:BusinessAcquisition

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities

synh:SynteractAcquisition


Business
Period End2020-12-09
Value98
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities100.0

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet us-gaap:BusinessAcquisition

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet

synh:SynteractAcquisition


Business
Period End2020-12-09
Value412
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet100.0

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther us-gaap:BusinessAcquisition

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther

synh:SynteractAcquisition


Business
Period End2020-12-09
Value1127000.0
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther100.0

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets us-gaap:BusinessAcquisition

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets

synh:SynteractAcquisition


Business
Period End2020-12-09
Value4121000.0
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets100.0

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment us-gaap:BusinessAcquisition

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment

synh:SynteractAcquisition


Business
Period End2020-12-09
Value3978000.0
Percentage of BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment100.0

us-gaap:CapitalLeaseObligationsCurrent

us-gaap:CapitalLeaseObligationsCurrent


Capital
Period End2021-06-302021-03-312020-12-312020-09-302019-12-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value17161716171316151516190.00.00.0530.1110.2540.4412.292
Percentage of CapitalLeaseObligationsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0

us-gaap:ContractWithCustomerAssetNetCurrent

us-gaap:ContractWithCustomerAssetNetCurrent


Contract
Period End2021-06-302021-03-312020-12-312020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value374372366128149109921051051361311110.0
Percentage of ContractWithCustomerAssetNetCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:DebtInstrumentCarryingAmount us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:DebtInstrumentCarryingAmount

synh:AccountsReceivableSecuritization, synh:AccountsReceivableFinancingAgreementDueOctober2022, us-gaap:SecuredDebt


Debt
Period End2021-06-302021-03-312020-12-312020-09-302019-12-31
Value365365300300275
Percentage of DebtInstrumentCarryingAmount100.0100.0100.0100.0100.0

us-gaap:DebtInstrumentCarryingAmount us-gaap:DebtInstrument, us-gaap:LongtermDebtType

synh:A2017CreditAgreementAmendmentNo2TermLoanADueMarch2024, us-gaap:SecuredDebt


Debt
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value1471153015501550115011501150975
Percentage of DebtInstrumentCarryingAmount490.40.00.0563.60.00.00.00.0

synh:A2017CreditAgreementAmendmentNo2TermLoanBDueAugust2024, us-gaap:SecuredDebt


Debt
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value49656076079579579586297710171221
Percentage of DebtInstrumentCarryingAmount136.0186.9253.50.00.0289.30.00.00.00.0

synh:A2017CreditAgreementTermLoanBDueAugust2024, us-gaap:SecuredDebt


Debt
Period End2020-12-312019-12-312018-12-312018-09-302018-06-302017-12-31
Value5607951221125114651550
Percentage of DebtInstrumentCarryingAmount186.9289.30.00.00.00.0

synh:TermLoanATrancheOneDueMarch2024, us-gaap:SecuredDebt


Debt
Period End2021-06-302021-03-312020-12-312019-12-31
Value1731731831550
Percentage of DebtInstrumentCarryingAmount47.647.661.2563.6

synh:TermLoanATrancheTwoDueAugust2024, us-gaap:SecuredDebt


Debt
Period End2021-06-302021-03-312020-12-31
Value173712421273
Percentage of DebtInstrumentCarryingAmount475.9340.3424.7

us-gaap:DebtInstrumentCarryingAmount us-gaap:LongtermDebtType

us-gaap:SecuredDebt


Debt
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312017-09-302016-12-31
Value227522772318253127512920262022872312236323652415245225502600500
Percentage of DebtInstrumentCarryingAmount623.6623.9772.8843.90.00.0952.90.00.00.00.00.00.00.00.00.0

us-gaap:UnsecuredDebt


Debt
Period End2021-06-302021-03-312020-12-312019-12-31
Value2875287729182620
Percentage of DebtInstrumentCarryingAmount787.9788.3972.8952.9

us-gaap:DebtInstrumentFaceAmount us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:DebtInstrumentFaceAmount

synh:IncrementalTermLoan, synh:CreditAgreementAmendmentNo5TermLoanA, us-gaap:SecuredDebt


Debt
Period End2021-06-30
Value495
Percentage of DebtInstrumentFaceAmount100.0

us-gaap:DebtInstrumentFaceAmount us-gaap:DebtInstrument, us-gaap:LongtermDebtType

synh:SeniorUnsecuredNotesDue2029, synh:ThreePointSixHundredTwentyFivePercentageSeniorNotes


Debt
Period End2020-11-24
Value600
Percentage of DebtInstrumentFaceAmount0.0

us-gaap:DebtInstrumentUnamortizedDiscount us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:DebtInstrumentUnamortizedDiscount

synh:TermLoan, synh:CreditAgreementAmendmentNo5TermLoanA, us-gaap:SecuredDebt


Debt
Period End2021-06-30
Value500000.0
Percentage of DebtInstrumentUnamortizedDiscount100.0

us-gaap:DebtInstrumentUnamortizedDiscountPremiumNet

us-gaap:DebtInstrumentUnamortizedDiscountPremiumNet


Debt
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312017-09-302016-12-31
Value3.0913.1083.53.8834.3124.624.928-27.178-28.25-29.305323334-38.656-32.3320.0
Percentage of DebtInstrumentUnamortizedDiscountPremiumNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:DebtInstrumentUnamortizedDiscountPremiumNet us-gaap:DebtInstrument

synh:SeniorUnsecuredNotesDue2029


Debt
Period End2020-12-31
Value3.5
Percentage of DebtInstrumentUnamortizedDiscountPremiumNet100.0

us-gaap:DebtLongtermAndShorttermCombinedAmount us-gaap:DebtInstrument, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:LongtermDebtType

us-gaap:DebtLongtermAndShorttermCombinedAmount

synh:A2017CreditAgreementAmendmentNo2TermLoanADueMarch2024, us-gaap:FairValueInputsLevel2, us-gaap:CarryingReportedAmountFairValueDisclosure, us-gaap:SecuredDebt


Debt
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value14541467152615451545114611461146973
Percentage of DebtLongtermAndShorttermCombinedAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0

synh:A2017CreditAgreementAmendmentNo2TermLoanATrancheOneDueMarch2024, us-gaap:FairValueInputsLevel2, us-gaap:CarryingReportedAmountFairValueDisclosure, us-gaap:SecuredDebt


Debt
Period End2021-06-302021-03-312020-12-31
Value173173183
Percentage of DebtLongtermAndShorttermCombinedAmount0.00.012.6

synh:A2017CreditAgreementAmendmentNo2TermLoanATrancheTwoDueAugust2024, us-gaap:FairValueInputsLevel2, us-gaap:CarryingReportedAmountFairValueDisclosure, us-gaap:SecuredDebt


Debt
Period End2021-06-302021-03-312020-12-31
Value173412391271
Percentage of DebtLongtermAndShorttermCombinedAmount0.00.087.4

synh:A2017CreditAgreementAmendmentNo2TermLoanBDueAugust2024, us-gaap:FairValueInputsLevel2, us-gaap:CarryingReportedAmountFairValueDisclosure, us-gaap:SecuredDebt


Debt
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value49656076079479479486197610161219
Percentage of DebtLongtermAndShorttermCombinedAmount0.038.551.852.151.451.475.185.288.7125.3

us-gaap:DecreaseInUnrecognizedTaxBenefitsIsReasonablyPossible

us-gaap:DecreaseInUnrecognizedTaxBenefitsIsReasonablyPossible


Decrease
Period End2020-12-31
Value1300000.0
Percentage of DecreaseInUnrecognizedTaxBenefitsIsReasonablyPossible100.0

us-gaap:DeferredCompensationLiabilityClassifiedNoncurrent

us-gaap:DeferredCompensationLiabilityClassifiedNoncurrent


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value222114150.0
Percentage of DeferredCompensationLiabilityClassifiedNoncurrent100.0100.0100.0100.00.0

us-gaap:DeferredFinanceCostsNet

us-gaap:DeferredFinanceCostsNet


Deferred
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312016-12-312016-09-302015-12-31
Value9.28211125.6986.3276.7227.1168.8819.3979.911131416202.2762.4213.161
Percentage of DeferredFinanceCostsNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredFinanceCostsNet us-gaap:CreditFacility, us-gaap:LongtermDebtType

synh:TermLoan, us-gaap:SecuredDebt


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312017-03-312016-12-31
Value127.1161320202.3
Percentage of DeferredFinanceCostsNet100.0100.0100.099.90.0101.1

us-gaap:DeferredIncomeTaxAssetsNet

us-gaap:DeferredIncomeTaxAssetsNet


Deferred
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-31
Value373435183434375.5029.1119.1539.31732322720212614
Percentage of DeferredIncomeTaxAssetsNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredIncomeTaxLiabilities

us-gaap:DeferredIncomeTaxLiabilities


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value28828725928746597591
Percentage of DeferredIncomeTaxLiabilities100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsCapitalLossCarryforwards

us-gaap:DeferredTaxAssetsCapitalLossCarryforwards


Deferred
Period End2020-12-31
Value20
Percentage of DeferredTaxAssetsCapitalLossCarryforwards100.0

us-gaap:DeferredTaxAssetsDeferredIncome

us-gaap:DeferredTaxAssetsDeferredIncome


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value771313154.632.8572.6834.644
Percentage of DeferredTaxAssetsDeferredIncome100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsGross

us-gaap:DeferredTaxAssetsGross


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value4033973934295860125125
Percentage of DeferredTaxAssetsGross100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsOperatingLossCarryforwards

us-gaap:DeferredTaxAssetsOperatingLossCarryforwards


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value12219926330812188086
Percentage of DeferredTaxAssetsOperatingLossCarryforwards100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsOther

us-gaap:DeferredTaxAssetsOther


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value7.913104.2022.6980.0680.2920.9320.207
Percentage of DeferredTaxAssetsOther100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsTaxCreditCarryforwards

us-gaap:DeferredTaxAssetsTaxCreditCarryforwards


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value585157554.69131513
Percentage of DeferredTaxAssetsTaxCreditCarryforwards100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value292727311815146.748
Percentage of DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities

us-gaap:DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value6.5268.508119.3065.284.9635.917.656
Percentage of DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts

us-gaap:DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value1739000.01091000.0963000.01975000.01660000.02162000.02058000.0490000.0
Percentage of DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxLiabilitiesOther

us-gaap:DeferredTaxLiabilitiesOther


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value2404000.0433000.03380000.01918000.01971000.00
Percentage of DeferredTaxLiabilitiesOther100.0100.0100.0100.0100.00.0

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value22622625027642567183
Percentage of DeferredTaxLiabilitiesPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxLiabilitiesUndistributedForeignEarnings

us-gaap:DeferredTaxLiabilitiesUndistributedForeignEarnings


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312017-08-012016-12-312015-12-312014-12-312013-12-31
Value103.43.8187.346530.00.4110.07.729
Percentage of DeferredTaxLiabilitiesUndistributedForeignEarnings100.0100.0100.0100.0100.00.0100.00.0100.0

us-gaap:DerivativeBasisSpreadOnVariableRate us-gaap:Range, us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:DerivativeBasisSpreadOnVariableRate

srt:Maximum, synh:TermLoan, synh:A2017CreditAgreementAmendmentNo2RevolvingCreditFacilityDueAugust2024, us-gaap:SecuredDebt


Derivative
Period End2021-02-28
Value1.5
Percentage of DerivativeBasisSpreadOnVariableRate100.0

srt:Minimum, synh:TermLoan, synh:A2017CreditAgreementAmendmentNo2RevolvingCreditFacilityDueAugust2024, us-gaap:SecuredDebt


Derivative
Period End2021-02-28
Value1.25
Percentage of DerivativeBasisSpreadOnVariableRate83.3

us-gaap:DerivativeLiabilities us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation

us-gaap:DerivativeLiabilities

us-gaap:InterestRateSwap, us-gaap:CashFlowHedging, us-gaap:DesignatedAsHedgingInstrument


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value8.363142229353417
Percentage of DerivativeLiabilities100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeLiabilities us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship

us-gaap:CashFlowHedging


Derivative
Period End2020-12-312019-12-31
Value2217
Percentage of DerivativeLiabilities100.0100.0

us-gaap:DerivativeLiabilities us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value8.3631422293534172121139.371.0281.933
Percentage of DerivativeLiabilities100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.0

us-gaap:DerivativeLiabilities us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsRecurring


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value8.3631422293534172121139.371.0281.933
Percentage of DerivativeLiabilities100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.0

us-gaap:DerivativeLiabilitiesCurrent us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship

us-gaap:DerivativeLiabilitiesCurrent

us-gaap:AccruedLiabilities, us-gaap:InterestRateSwap, us-gaap:CashFlowHedging


Derivative
Period End2020-12-312019-12-31
Value1711
Percentage of DerivativeLiabilitiesCurrent100.0100.0

us-gaap:DerivativeLiabilitiesCurrent us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation

us-gaap:AccruedLiabilities, us-gaap:InterestRateSwap, us-gaap:CashFlowHedging, us-gaap:DesignatedAsHedgingInstrument


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value6.212111722272411119.1724.3283.0311.0281.590.0
Percentage of DerivativeLiabilitiesCurrent0.00.0100.00.00.00.0100.00.00.00.00.00.00.00.0

us-gaap:DerivativeLiabilitiesNoncurrent us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship

us-gaap:DerivativeLiabilitiesNoncurrent

us-gaap:OtherNoncurrentLiabilities, us-gaap:InterestRateSwap, us-gaap:CashFlowHedging


Derivative
Period End2020-12-312019-12-31
Value5.5726.095
Percentage of DerivativeLiabilitiesNoncurrent100.0100.0

us-gaap:DerivativeLiabilitiesNoncurrent us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation

us-gaap:OtherNoncurrentLiabilities, us-gaap:InterestRateSwap, us-gaap:CashFlowHedging, us-gaap:DesignatedAsHedgingInstrument


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-06-302017-12-31
Value2.1513.1615.5726.9798.1549.8986.09510128.8326.2010.3430.0
Percentage of DerivativeLiabilitiesNoncurrent0.00.0100.00.00.00.0100.00.00.00.00.00.00.0

us-gaap:DerivativeNotionalAmount

us-gaap:DerivativeNotionalAmount


Derivative
Period End2020-12-31
Value0.9056
Percentage of DerivativeNotionalAmount100.0

us-gaap:DerivativeNotionalAmount us-gaap:DerivativeInstrumentRisk

synh:InterestRateSwapExpiringJune302021


Derivative
Period End2021-03-312020-09-302020-06-302018-12-312018-06-30
Value89491792810101010
Percentage of DerivativeNotionalAmount0.00.00.00.00.0

synh:InterestRateSwapExpiringMarch312023


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value1420572603573604549
Percentage of DerivativeNotionalAmount0.00.066607.80.00.00.0

us-gaap:ForeignExchangeForward


Derivative
Period End2021-06-302021-03-312020-12-31
Value655050
Percentage of DerivativeNotionalAmount0.00.05521.2

us-gaap:DisposalGroupIncludingDiscontinuedOperationConsideration us-gaap:StatementBusinessSegments

us-gaap:DisposalGroupIncludingDiscontinuedOperationConsideration

synh:ClinicalSolutionsSegment


Disposal
Period End2020-12-31
Value23
Percentage of DisposalGroupIncludingDiscontinuedOperationConsideration100.0

us-gaap:EmployeeRelatedLiabilitiesCurrent

us-gaap:EmployeeRelatedLiabilitiesCurrent


Employee
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302016-12-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value25519519321522277716253546442
Percentage of EmployeeRelatedLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions us-gaap:AwardType

us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions

us-gaap:RestrictedStockUnitsRSU


Employee
Period End2020-12-31
Value62400.0
Percentage of EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions100.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue


Fair
Period End2021-06-302020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-312016-12-31
Value0.9956.7936.6416.496.383719192020500.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:FinanceLeaseLiability

us-gaap:FinanceLeaseLiability


Finance
Period End2020-12-312019-12-312019-09-302019-06-30
Value48545444
Percentage of FinanceLeaseLiability100.0100.0100.0100.0

us-gaap:FinanceLeaseLiabilityCurrent

us-gaap:FinanceLeaseLiabilityCurrent


Finance
Period End2020-12-312020-09-302019-12-312019-09-302019-06-30
Value170.0171716
Percentage of FinanceLeaseLiabilityCurrent100.00.0100.0100.0100.0

us-gaap:FinanceLeaseLiabilityNoncurrent

us-gaap:FinanceLeaseLiabilityNoncurrent


Finance
Period End2021-06-302021-03-312020-12-312020-09-302019-12-312019-09-302019-06-30
Value25273128363628
Percentage of FinanceLeaseLiabilityNoncurrent100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinanceLeaseLiabilityPaymentsDue

us-gaap:FinanceLeaseLiabilityPaymentsDue


Finance
Period End2020-12-31
Value50
Percentage of FinanceLeaseLiabilityPaymentsDue100.0

us-gaap:FinanceLeaseLiabilityPaymentsDueNextTwelveMonths

us-gaap:FinanceLeaseLiabilityPaymentsDueNextTwelveMonths


Finance
Period End2020-12-31
Value18
Percentage of FinanceLeaseLiabilityPaymentsDueNextTwelveMonths100.0

us-gaap:FinanceLeaseLiabilityPaymentsDueYearFive

us-gaap:FinanceLeaseLiabilityPaymentsDueYearFive


Finance
Period End2020-12-31
Value14000.0
Percentage of FinanceLeaseLiabilityPaymentsDueYearFive100.0

us-gaap:FinanceLeaseLiabilityPaymentsDueYearFour

us-gaap:FinanceLeaseLiabilityPaymentsDueYearFour


Finance
Period End2020-12-31
Value4176000.0
Percentage of FinanceLeaseLiabilityPaymentsDueYearFour100.0

us-gaap:FinanceLeaseLiabilityPaymentsDueYearThree

us-gaap:FinanceLeaseLiabilityPaymentsDueYearThree


Finance
Period End2020-12-31
Value10
Percentage of FinanceLeaseLiabilityPaymentsDueYearThree100.0

us-gaap:FinanceLeaseLiabilityPaymentsDueYearTwo

us-gaap:FinanceLeaseLiabilityPaymentsDueYearTwo


Finance
Period End2020-12-31
Value17
Percentage of FinanceLeaseLiabilityPaymentsDueYearTwo100.0

us-gaap:FinanceLeaseLiabilityUndiscountedExcessAmount

us-gaap:FinanceLeaseLiabilityUndiscountedExcessAmount


Finance
Period End2020-12-31
Value1155000.0
Percentage of FinanceLeaseLiabilityUndiscountedExcessAmount100.0

us-gaap:FinanceLeaseRightOfUseAsset

us-gaap:FinanceLeaseRightOfUseAsset


Finance
Period End2020-12-312019-12-31
Value4349
Percentage of FinanceLeaseRightOfUseAsset100.0100.0

us-gaap:FinanceLeaseWeightedAverageDiscountRatePercent

us-gaap:FinanceLeaseWeightedAverageDiscountRatePercent


Finance
Period End2020-12-312019-12-31
Value1.32.9
Percentage of FinanceLeaseWeightedAverageDiscountRatePercent100.0100.0

us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization

us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization


Finite
Period End2020-12-312019-12-312018-12-312018-09-302017-12-312017-09-302016-12-312015-12-312014-12-312013-12-31
Value841686518468323258188150114154
Percentage of FiniteLivedIntangibleAssetsAccumulatedAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:CustomerRelationships


Finite
Period End2020-12-312019-12-312018-12-312018-09-302017-12-312017-09-302016-12-312015-12-312014-12-312013-12-31
Value68554640336826623018815011273
Percentage of FiniteLivedIntangibleAssetsAccumulatedAmortization81.479.777.978.882.189.2100.0100.098.047.8

us-gaap:IntellectualProperty


Finite
Period End2020-12-31
Value1.668
Percentage of FiniteLivedIntangibleAssetsAccumulatedAmortization0.2

us-gaap:OrderOrProductionBacklog


Finite
Period End2020-12-312019-12-312018-12-312018-09-302017-12-312017-09-302016-12-312015-12-312014-12-312013-12-31
Value1321211008642210.00.02.04974
Percentage of FiniteLivedIntangibleAssetsAccumulatedAmortization15.817.719.418.413.08.50.00.01.848.5

us-gaap:TrademarksAndTradeNames


Finite
Period End2020-12-312019-12-31
Value2117
Percentage of FiniteLivedIntangibleAssetsAccumulatedAmortization2.62.6

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive


Finite
Period End2020-12-31
Value239
Percentage of FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive100.0

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths


Finite
Period End2020-12-31
Value157
Percentage of FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths100.0

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFive

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFive


Finite
Period End2020-12-31
Value118
Percentage of FiniteLivedIntangibleAssetsAmortizationExpenseYearFive100.0

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFour

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFour


Finite
Period End2020-12-31
Value132
Percentage of FiniteLivedIntangibleAssetsAmortizationExpenseYearFour100.0

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearThree

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearThree


Finite
Period End2020-12-31
Value139
Percentage of FiniteLivedIntangibleAssetsAmortizationExpenseYearThree100.0

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo


Finite
Period End2020-12-31
Value146
Percentage of FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo100.0

us-gaap:FiniteLivedIntangibleAssetsGross

us-gaap:FiniteLivedIntangibleAssetsGross


Finite
Period End2020-12-312019-12-312018-12-312018-09-302017-12-312017-09-302017-03-312016-12-312015-12-312014-12-312013-12-31
Value1774165916521657161016531610267267270350
Percentage of FiniteLivedIntangibleAssetsGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FiniteLivedIntangibleAssetsGross us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:CustomerRelationships


Finite
Period End2020-12-312019-12-312018-12-312018-09-302017-12-312017-09-302016-12-312015-12-312014-12-312013-12-31
Value151814911484148914401373267267267268
Percentage of FiniteLivedIntangibleAssetsGross85.589.989.989.989.483.1100.0100.099.176.6

us-gaap:IntellectualProperty


Finite
Period End2020-12-31
Value30
Percentage of FiniteLivedIntangibleAssetsGross1.7

us-gaap:OrderOrProductionBacklog


Finite
Period End2020-12-312019-12-312018-12-312018-09-302017-12-312017-09-302016-12-312015-12-312014-12-312013-12-31
Value1741361361361372470.00.02.04976
Percentage of FiniteLivedIntangibleAssetsGross9.88.38.38.38.515.00.00.00.821.7

us-gaap:TrademarksAndTradeNames


Finite
Period End2020-12-312019-12-31
Value5231
Percentage of FiniteLivedIntangibleAssetsGross3.01.9

us-gaap:GoodwillImpairedAccumulatedImpairmentLoss us-gaap:StatementBusinessSegments

us-gaap:GoodwillImpairedAccumulatedImpairmentLoss

synh:ClinicalSolutionsSegment


Goodwill
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-31
Value8.18.18.18.18.18.18.18.18.1428.1428.1428.1428.1428.1428.1428.1428.142
Percentage of GoodwillImpairedAccumulatedImpairmentLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

synh:CommercialSolutionsSegment


Goodwill
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302019-12-312019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-31
Value8.08.08.08.08.08.08.0248.0248.0248.0248.0248.0248.0248.0248.024
Percentage of GoodwillImpairedAccumulatedImpairmentLoss98.898.898.898.898.898.898.698.698.698.698.698.698.698.698.6

us-gaap:InterestPayableCurrent

us-gaap:InterestPayableCurrent


Interest
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302016-12-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value170.7878.2789.399160.0720.3680.4130.552.4922.67819
Percentage of InterestPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths


Lessee
Period End2020-12-31
Value54
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths100.0

us-gaap:LiabilitiesFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:LiabilitiesFairValueDisclosure

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value8.3631422293534172121139.371.0281.9330.00.0
Percentage of LiabilitiesFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0

us-gaap:FairValueInputsLevel3, us-gaap:FairValueMeasurementsRecurring


Liabilities
Period End2021-06-302020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value0.9956.7936.6416.496.38371919202058525150
Percentage of LiabilitiesFairValueDisclosure11.930.022.818.218.4213.990.088.5159.3214.85693.62735.00.00.0

us-gaap:LiabilitiesFairValueDisclosure us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsRecurring


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value9.3581429354241544040342959545150
Percentage of LiabilitiesFairValueDisclosure111.9100.0130.0122.8118.2118.4313.9190.0188.5259.3314.85793.62835.00.00.0

us-gaap:LineOfCredit us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:LineOfCredit

us-gaap:LetterOfCredit, synh:A2017CreditAgreementRevolvingCreditFacilityDueAugust2022, us-gaap:SecuredDebt


Line
Period End2020-12-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value16181919191918
Percentage of LineOfCredit100.0100.0100.0100.0100.0100.0100.0

us-gaap:LetterOfCredit, synh:A2017CreditAgreementRevolvingCreditFacilityDueAugust2024, us-gaap:SecuredDebt


Line
Period End2021-06-302021-03-312020-09-302020-06-30
Value16161818
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Line
Period End2020-07-31
Value150
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us-gaap:LineOfCredit us-gaap:CreditFacility, us-gaap:LongtermDebtType

us-gaap:RevolvingCreditFacility, us-gaap:SecuredDebt


Line
Period End2020-09-30
Value150
Percentage of LineOfCredit0.0

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us-gaap:LineOfCreditFacilityCapacityAvailableForTradePurchases

us-gaap:LetterOfCredit, us-gaap:SecuredDebt


Line
Period End2021-06-302021-03-312020-09-30
Value133133131
Percentage of LineOfCreditFacilityCapacityAvailableForTradePurchases100.0100.0100.0

us-gaap:LineOfCreditFacilityInterestRateAtPeriodEnd us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:LineOfCreditFacilityInterestRateAtPeriodEnd

synh:TermLoan, synh:A2017CreditAgreementAmendmentNo2TermLoanBDueAugust2024, us-gaap:SecuredDebt


Line
Period End2020-12-312019-12-31
Value1.8960.03799
Percentage of LineOfCreditFacilityInterestRateAtPeriodEnd100.0100.0

us-gaap:RevolvingCreditFacility, synh:A2017CreditAgreementRevolvingCreditFacilityDueAugust2022, us-gaap:SecuredDebt


Line
Period End2020-12-312019-12-312018-12-312017-12-31
Value1.6460.032990.040220.03319
Percentage of LineOfCreditFacilityInterestRateAtPeriodEnd86.886.80.00.0

us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity us-gaap:ConsolidatedEntities, us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity

srt:Subsidiaries, synh:AccountsReceivableSecuritization, synh:AccountsReceivableFinancingAgreementDueOctober2022, us-gaap:SecuredDebt


Line
Period End2021-01-282021-01-272020-09-252020-09-24
Value365300300275
Percentage of LineOfCreditFacilityMaximumBorrowingCapacity100.0100.0100.0100.0

us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity

us-gaap:RevolvingCreditFacility, synh:A2017CreditAgreementRevolvingCreditFacilityDueAugust2022, us-gaap:SecuredDebt


Line
Period End2020-12-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value584581580580580480
Percentage of LineOfCreditFacilityRemainingBorrowingCapacity100.0100.0100.0100.0100.0100.0

us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity us-gaap:DebtInstrument, us-gaap:LongtermDebtType

synh:A2017CreditAgreementRevolvingCreditFacilityDueAugust2024, us-gaap:SecuredDebt


Line
Period End2021-06-302021-03-312020-09-302020-06-30
Value583583581431
Percentage of LineOfCreditFacilityRemainingBorrowingCapacity0.00.00.00.0

us-gaap:LongTermDebtFairValue us-gaap:DebtInstrument, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:LongtermDebtType

us-gaap:LongTermDebtFairValue

synh:A2017CreditAgreementAmendmentNo2TermLoanADueMarch2024, us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:SecuredDebt


Long
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value14521452148414431550115011501150975
Percentage of LongTermDebtFairValue100.0100.0100.0100.0100.0100.0100.0100.0100.0

synh:A2017CreditAgreementAmendmentNo2TermLoanATrancheOneDueMarch2024, us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:SecuredDebt


Long
Period End2021-06-302021-03-312020-12-31
Value173173183
Percentage of LongTermDebtFairValue0.00.012.6

synh:A2017CreditAgreementAmendmentNo2TermLoanATrancheTwoDueAugust2024, us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:SecuredDebt


Long
Period End2021-06-302021-03-312020-12-31
Value174112431269
Percentage of LongTermDebtFairValue0.00.087.4

synh:A2017CreditAgreementAmendmentNo2TermLoanBDueAugust2024, us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:SecuredDebt


Long
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value49756075177177579586297710171221
Percentage of LongTermDebtFairValue0.038.651.752.053.751.375.085.088.5125.2

synh:SeniorUnsecuredNoteDue2029, us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:UnsecuredDebt


Long
Period End2021-06-302021-03-312020-12-31
Value598586602
Percentage of LongTermDebtFairValue0.00.041.5

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive


Long
Period End2020-09-30
Value1845
Percentage of LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive100.0

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour


Long
Period End2021-06-302021-03-312020-12-312020-09-30
Value176417841848155
Percentage of LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour100.0100.0100.0100.0

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree


Long
Period End2021-06-302021-03-312020-12-312020-09-30
Value125107107445
Percentage of LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree100.0100.0100.0100.0

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo


Long
Period End2021-06-302021-03-312020-12-312020-09-30
Value38538536285
Percentage of LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo100.0100.0100.0100.0

us-gaap:OperatingLeaseWeightedAverageDiscountRatePercent

us-gaap:OperatingLeaseWeightedAverageDiscountRatePercent


Operating
Period End2020-12-312019-12-31
Value4.85.0
Percentage of OperatingLeaseWeightedAverageDiscountRatePercent100.0100.0

us-gaap:OperatingLossCarryforwards us-gaap:IncomeTaxAuthority

us-gaap:OperatingLossCarryforwards

us-gaap:DomesticCountry


Operating
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value26056984610005.439185191
Percentage of OperatingLossCarryforwards100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ForeignCountry


Operating
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value8085118124547083113
Percentage of OperatingLossCarryforwards30.715.114.012.51005.6180.545.259.1

us-gaap:StateAndLocalJurisdiction


Operating
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value82110401030120052121263239
Percentage of OperatingLossCarryforwards315.0182.6121.7120.0963.0312.6142.2125.0

us-gaap:OtherLongTermInvestments

us-gaap:OtherLongTermInvestments


Other
Period End2021-06-30
Value24
Percentage of OtherLongTermInvestments100.0

us-gaap:PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization us-gaap:PropertyPlantAndEquipmentByType

us-gaap:PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization

us-gaap:Vehicles


Property
Period End2020-12-312019-12-31
Value2020
Percentage of PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization100.0100.0

us-gaap:PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization us-gaap:PropertyPlantAndEquipmentByType

us-gaap:PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization

us-gaap:Vehicles


Property
Period End2020-12-312019-12-31
Value1516
Percentage of PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization100.0100.0

us-gaap:PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization

us-gaap:PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization


Property
Period End2020-12-312019-12-31
Value6370
Percentage of PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization100.0100.0

us-gaap:PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization us-gaap:PropertyPlantAndEquipmentByType

us-gaap:Vehicles


Property
Period End2020-12-312019-12-31
Value6470
Percentage of PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization100.099.9

us-gaap:PurchaseObligation us-gaap:SubsequentEventType

us-gaap:PurchaseObligation

us-gaap:SubsequentEvent


Purchase
Period End2020-10-26
Value400
Percentage of PurchaseObligation100.0

us-gaap:RestrictedCashCurrent

us-gaap:RestrictedCashCurrent


Restricted
Period End2020-12-312019-12-312018-12-312018-09-302018-06-302018-01-012017-12-31
Value300000.0500000.02069000.02202000.02191000.0714000.0714000.0
Percentage of RestrictedCashCurrent100.0100.0100.0100.0100.0100.0100.0

us-gaap:RestructuringReserveCurrent

us-gaap:RestructuringReserveCurrent


Restructuring
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302016-12-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value5.835.751013156.0842.231.9123.5781.9031.7772.094
Percentage of RestructuringReserveCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueRemainingPerformanceObligation

us-gaap:RevenueRemainingPerformanceObligation


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302019-12-31
Value71506930720057605400
Percentage of RevenueRemainingPerformanceObligation100.0100.0100.0100.0100.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue us-gaap:AwardType

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue

us-gaap:RestrictedStockUnitsRSU


Share
Period End2020-12-312019-12-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value51.443.4841.0240.9340.8541.4449.342.7641.6724.610
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice us-gaap:AwardType

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice

us-gaap:EmployeeStockOption


Share
Period End2020-12-31
Value30.12
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice100.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue us-gaap:AwardType

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue

us-gaap:EmployeeStockOption


Share
Period End2020-12-31
Value25
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue100.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue us-gaap:AwardType

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue

us-gaap:EmployeeStockOption


Share
Period End2020-12-31
Value25
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue100.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice us-gaap:AwardType

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice

us-gaap:EmployeeStockOption


Share
Period End2020-12-31
Value30.12
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice100.0

us-gaap:SharePrice us-gaap:StatementClassOfStock

us-gaap:SharePrice

us-gaap:CommonStock


Share
Period End2020-12-31
Value68.13
Percentage of SharePrice100.0

us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1 us-gaap:AwardType

us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1

us-gaap:EmployeeStockOption


Sharebased
Period End2020-12-31
Value25
Percentage of SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1100.0

us-gaap:StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1 us-gaap:StatementClassOfStock

us-gaap:StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1

us-gaap:CommonStock


Stock
Period End2021-06-302021-03-312020-09-30
Value182255106
Percentage of StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1100.0100.0100.0

us-gaap:TaxCreditCarryforwardAmount us-gaap:IncomeTaxAuthorityName, us-gaap:TaxCreditCarryforward

us-gaap:TaxCreditCarryforwardAmount

us-gaap:CanadaRevenueAgency, us-gaap:Research


Tax
Period End2020-12-312019-12-312018-12-312017-12-31
Value56485154
Percentage of TaxCreditCarryforwardAmount100.0100.0100.0100.0

us-gaap:TaxCreditCarryforwardValuationAllowance us-gaap:IncomeTaxAuthorityName, us-gaap:TaxCreditCarryforward

us-gaap:TaxCreditCarryforwardValuationAllowance

us-gaap:CanadaRevenueAgency, us-gaap:Research


Tax
Period End2020-12-312019-12-312018-12-312017-12-31
Value56484850
Percentage of TaxCreditCarryforwardValuationAllowance100.0100.0100.0100.0

us-gaap:TradingSecurities us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:TradingSecurities

us-gaap:FairValueInputsLevel1, us-gaap:FairValueMeasurementsRecurring


Trading
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value24232220191821212120141716161615
Percentage of TradingSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:TradingSecurities us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsRecurring


Trading
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value24232220191821212120141716161615
Percentage of TradingSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:UnbilledReceivablesCurrent

us-gaap:UnbilledReceivablesCurrent


Unbilled
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-01-012017-12-31
Value234228577609522447372416419392422347346220373
Percentage of UnbilledReceivablesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued

us-gaap:UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued


Unrecognized
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-312014-12-312013-12-31
Value2800000.06400000.04400000.05000000.04600000.0300000.0100000.0100000.02100000.02600000.01900000.0
Percentage of UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ValuationAllowancesAndReservesBalance

us-gaap:ValuationAllowancesAndReservesBalance


Valuation
Period End2020-12-312019-12-312018-12-312017-12-312017-03-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-31
Value7.6155.3814.5879.0769.0765.8843.5573.7271.3841.7482.148
Percentage of ValuationAllowancesAndReservesBalance100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ValuationAllowancesAndReservesBalance us-gaap:RestructuringCostAndReserve, us-gaap:ValuationAllowancesAndReservesType

synh:EmployeeSeveranceCostsIncludingExecutiveTransitionCosts, us-gaap:BusinessRestructuringReserves


Valuation
Period End2020-12-312019-12-312019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-31
Value5.835.728157.4745.4797.6097.9198.8584.6951.0650.0
Percentage of ValuationAllowancesAndReservesBalance76.6106.40.0162.90.00.00.097.679.829.90.0

us-gaap:EmployeeSeverance, us-gaap:BusinessRestructuringReserves


Valuation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302018-12-31
Value3.3773.4075.834.6976.0894.3155.728104.9377.474
Percentage of ValuationAllowancesAndReservesBalance0.00.076.60.00.00.0106.40.00.0162.9

us-gaap:ValuationAllowancesAndReservesBalance us-gaap:ValuationAllowancesAndReservesType

us-gaap:BusinessRestructuringReserves


Valuation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-312014-12-31
Value3.3773.4075.834.6976.0894.3375.75104.959152426131516207.6256.9998.5924.7266.144
Percentage of ValuationAllowancesAndReservesBalance0.00.076.60.00.00.0106.90.00.00.0529.50.00.00.0185.00.00.077.1146.0132.9164.9

us-gaap:ValuationAllowanceOfDeferredTaxAssets


Valuation
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-31
Value100841501595.2381648463635
Percentage of ValuationAllowancesAndReservesBalance1317.31564.03277.01759.089.0470.41305.63357.02108.71670.6

Line plots across dimensions of each concept


COGS Ratio
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
('us-gaap:OperatingSegments', None)
C O G S  Ratious-gaap: Consolidation Items, us-gaap: Statement Business Segments
Operating Margin
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
('us-gaap:OperatingSegments', None)
Operating  Marginus-gaap: Consolidation Items, us-gaap: Statement Business Segments
SG&A Ratio
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
('us-gaap:OperatingSegments', None)
S G& A  Ratious-gaap: Consolidation Items, us-gaap: Statement Business Segments
TTM Greenblatt ROC
_
(None,)
T T M  Greenblatt  R O C_
us-gaap:AllocatedShareBasedCompensationExpense
us-gaap:ConsolidationItems, us-gaap:IncomeStatementLocation
('us-gaap:CorporateNonSegment', None)
Allocated Share Based Compensation Expenseus-gaap: Consolidation Items, us-gaap: Income Statement Location
us-gaap:CostOfGoodsAndServicesSold
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
('us-gaap:OperatingSegments', None)
Cost Of Goods And Services Soldus-gaap: Consolidation Items, us-gaap: Statement Business Segments
us-gaap:OperatingIncomeLoss
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
('us-gaap:OperatingSegments', None)
Operating Income Lossus-gaap: Consolidation Items, us-gaap: Statement Business Segments
us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
('us-gaap:OperatingSegments', None)
Revenue From Contract With Customer Excluding Assessed Taxus-gaap: Consolidation Items, us-gaap: Statement Business Segments
us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax
us-gaap:StatementGeographical
(None,)
Revenue From Contract With Customer Excluding Assessed Taxus-gaap: Statement Geographical
us-gaap:SellingGeneralAndAdministrativeExpense
us-gaap:ConsolidationItems
(None,)
Selling General And Administrative Expenseus-gaap: Consolidation Items
us-gaap:SellingGeneralAndAdministrativeExpense
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
('us-gaap:OperatingSegments', None)
Selling General And Administrative Expenseus-gaap: Consolidation Items, us-gaap: Statement Business Segments
us-gaap:StockholdersEquity
us-gaap:StatementEquityComponents
(None,)
Stockholders Equityus-gaap: Statement Equity Components
us-gaap:PropertyPlantAndEquipmentGross
us-gaap:PropertyPlantAndEquipmentByType
(None,)
Property Plant And Equipment Grossus-gaap: Property Plant And Equipment By Type
us-gaap:PropertyPlantAndEquipmentNet
us-gaap:StatementGeographical
(None,)
Property Plant And Equipment Netus-gaap: Statement Geographical
us-gaap:Goodwill
us-gaap:StatementBusinessSegments
(None,)
Goodwillus-gaap: Statement Business Segments
us-gaap:FiniteLivedIntangibleAssetsNet
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
(None,)
Finite Lived Intangible Assets Netus-gaap: Finite Lived Intangible Assets By Major Class
us-gaap:StockholdersEquity
us-gaap:StatementEquityComponents
(None,)
Stockholders Equityus-gaap: Statement Equity Components
us-gaap:StockIssuedDuringPeriodValueNewIssues
us-gaap:StatementEquityComponents
(None,)
Stock Issued During Period Value New Issuesus-gaap: Statement Equity Components
us-gaap:RepaymentsOfLongTermDebt
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
(None, 'us-gaap:SecuredDebt')
Repayments Of Long Term Debtus-gaap: Debt Instrument, us-gaap: Longterm Debt Type