0001280784July 2024January 2022 December 2023Q3July 2024May 2023July 2024July 2024falseJune 2025--12-312022July 2024July 20240001280784htgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:UnsecuredDebtElevenPointFiveZeroPercentageMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:DiversifiedFinancialServicesMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerMemberhtgc:ControlAndAffiliateInvestmentsMember2021-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:EsentireIncorporationMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:DebtInvestmentsMemberhtgc:CarbonHealthTechnologiesIncMember2022-09-300001280784htgc:AutomationAnyWhereIncMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:ViridianTherapeuticsIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:LandingHoldingsIncMember2022-01-012022-09-300001280784htgc:InvestmentByAssetMember2022-01-012022-09-300001280784htgc:BrightMachinesIncorporationMemberhtgc:ManufacturingTechnologyMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-09-3000012807842017-10-230001280784us-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberus-gaap:PreferredStockMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:BlackCrowAIIncMember2021-12-310001280784htgc:UnusedFacilityOtherFeesMember2022-01-012022-09-300001280784htgc:DrugDeliveryMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:BioQPharmaIncorporatedMember2021-01-012021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:CenterForBreakthroughMedicinesHoldingsLLCMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:MarchTwoThousandTwentySixBNotesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2021-12-310001280784htgc:JuneTwoThousandTwentyFiveThreeYearNotesMember2022-01-012022-09-300001280784us-gaap:GeographicConcentrationRiskMemberus-gaap:SalesRevenueNetMembercountry:IL2021-01-012021-12-310001280784us-gaap:FairValueInputsLevel1Memberus-gaap:CommonStockMemberus-gaap:FairValueMeasurementsRecurringMember2022-09-300001280784htgc:SBADebenturesIssuedOnMarchTwentySixTwoThousandAndTwentyOneMember2022-09-300001280784htgc:DelphixCorporationMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberus-gaap:SeriesCPreferredStockMemberhtgc:ShareThisIncMemberhtgc:WarrantInvestmentMember2021-01-012021-12-310001280784us-gaap:WarrantMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2021-12-310001280784htgc:JuneTwoThousandTwentyFiveNotesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2021-12-310001280784htgc:PharmaceuticalsMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputHypotheticalMarketYieldMembersrt:WeightedAverageMemberhtgc:MarketComparableCompaniesMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:CloudNineSoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMember2021-12-310001280784htgc:LiabilityClassifiedAwardsMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:AlladaptImmunotherapeuticsincMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:InvestmentFundsAndVehiclesMemberhtgc:ForbionGrowthOpportunitiesFundIICVMember2021-12-310001280784htgc:XFourPharmaceuticalsIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:TwoThousandTwentyEightAssetBackedNotesMemberhtgc:UnusedFacilityOtherFeesMember2021-07-012021-09-300001280784htgc:JuneTwoThousandTwentyFiveNotesMemberhtgc:UnusedFacilityOtherFeesMember2022-07-012022-09-300001280784htgc:ServiceVestingAwardsMember2021-01-012021-09-300001280784htgc:JulyTwoThousandTwentyFourNotesMember2022-07-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:ImpervaIncMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:AlladaptImmunotherapeuticsincMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:ModumetalIncMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:SustainableAndRenewableTechnologyMember2022-01-012022-09-300001280784htgc:EquityInvestmentsMemberus-gaap:SeriesDPreferredStockMemberhtgc:SustainableAndRenewableTechnologyMemberhtgc:PivotBioIncMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:SkywordIncorporatinMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesBPreferredStockMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:GibraltarBusinessCapitalLLCMemberus-gaap:UnsecuredDebtMemberhtgc:MajorityOwnedControlInvestmentsMember2021-12-310001280784htgc:SeriesAAPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:FlowonixMedicalIncorporatedMemberhtgc:MedicalDevicesAndEquipmentMember2021-01-012021-12-310001280784htgc:DebtInvestmentsMemberhtgc:ZimperiumIncMember2021-12-310001280784htgc:UnusedFacilityOtherFeesMemberhtgc:TwoThousandTwentySevenAssetBackedNotesMember2021-07-012021-09-300001280784htgc:OtherMemberus-gaap:GeographicConcentrationRiskMemberus-gaap:SalesRevenueNetMember2022-01-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:GenoceaBiosciencesIncMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2021-12-310001280784htgc:PineappleEnergyLLCMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WorldremitGroupLimitedMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesDPreferredStockMember2022-01-012022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:MajorityOwnedControlInvestmentsMemberus-gaap:UnsecuredDebtMember2020-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:MajorityOwnedControlInvestmentsMemberus-gaap:UnsecuredDebtMember2021-09-300001280784us-gaap:EquitySecuritiesMemberhtgc:ValuationTechniqueLiquidationMemberus-gaap:FairValueInputsLevel3Member2021-12-310001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMemberhtgc:UdacityIncMember2022-01-012022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberus-gaap:SeriesCPreferredStockMemberhtgc:LogicSourceMemberhtgc:WarrantInvestmentMember2021-12-310001280784htgc:EquityInvestmentsMemberhtgc:TwentyThreeAndMeIncMemberhtgc:HealthcareServicesOtherMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784us-gaap:FairValueInputsLevel2Memberus-gaap:EstimateOfFairValueFairValueDisclosureMember2021-12-310001280784htgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:SoftwareMemberhtgc:DockerIncMember2021-01-012021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:SolarSpectrumHoldingsLLCMember2021-01-012021-09-300001280784htgc:UnusedFacilityOtherFeesMemberhtgc:MarchTwoThousandTwentySixBNotesMember2022-01-012022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:SeniorDebtMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2021-01-012021-09-300001280784us-gaap:MeasurementInputDiscountForLackOfMarketabilityMemberus-gaap:EquitySecuritiesMemberhtgc:ValuationTechniqueLiquidationMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:JobandtalentUSAIncorporationMemberhtgc:ExitFeeMember2022-09-300001280784htgc:IvericBioGeneTherapyLlcMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:MobileSolutionsServicesMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:EquityInvestmentsMemberhtgc:SeriesAThreePreferredStockMemberhtgc:CapLinkedIncMemberhtgc:SoftwareMember2022-09-300001280784htgc:HerculesAdviserLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMember2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:TarsusPharmaceuticalsIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:SalaryComLlcMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:DermavantSciencesLtdMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:CommunicationsAndNetworkingMemberhtgc:AryakaNetworksIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:DashlaneIncorporationMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:TricidaIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:ZoomMediaGroupIncMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesAPreferredStockMemberhtgc:MediaContentInfoMember2022-09-300001280784htgc:GryphonNetworksCorporationMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:ConsumerAndBusinessProductsMemberhtgc:TechStyleIncMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesBPreferredStockMember2022-09-300001280784us-gaap:FairValueInputsLevel1Memberus-gaap:CommonStockMember2021-12-310001280784htgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:SoftwareMemberhtgc:DockerIncMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:CopperCRMIncorporationMemberhtgc:ExitFeeMember2022-09-300001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:MedicalDevicesAndEquipmentMemberhtgc:TelaBioIncMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:SnagajobcomIncMemberhtgc:WarrantInvestmentMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:CenturyTherapeuticsIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:SeniorsecuredtranchecMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:TecturaCorporationMember2021-12-310001280784htgc:UnusedFacilityOtherFeesMemberhtgc:MarchTwoThousandTwentySixBNotesMember2022-07-012022-09-300001280784htgc:JuneTwoThousandTwentyFiveThreeYearNotesMemberhtgc:UnusedFacilityOtherFeesMember2022-07-012022-09-300001280784htgc:SMBCFacilityMemberus-gaap:FairValueInputsLevel3Memberus-gaap:EstimateOfFairValueFairValueDisclosureMember2021-12-310001280784htgc:MarchTwoThousandTwentySixBNotesMemberus-gaap:FairValueInputsLevel3Memberus-gaap:EstimateOfFairValueFairValueDisclosureMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:TecturaCorporationMember2021-12-310001280784htgc:DrugDeliveryMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:PDSBiotechnologyCorporationMember2021-12-3100012807842022-06-300001280784htgc:InternetConsumerAndBusinessServicesMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:SeniorsecuredtranchecMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2021-01-012021-12-310001280784us-gaap:FairValueInputsLevel1Memberus-gaap:CommonStockMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:DynavaxTechnologiesMember2022-01-012022-09-300001280784htgc:TwoThousandThirtyThreeNotesMember2022-01-012022-09-300001280784htgc:GroveCollaborativeIncMemberhtgc:ConsumerAndBusinessProductsMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:HerculesAdviserLLCMemberus-gaap:MemberUnitsMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:MajorityOwnedControlInvestmentsMember2021-12-310001280784htgc:WarrantInvestmentMemberhtgc:SoftwareMemberhtgc:SeriesJuniorOnePreferredMemberhtgc:SignPostIncMember2021-12-310001280784us-gaap:EquitySecuritiesMembersrt:MinimumMemberus-gaap:ValuationTechniqueOptionPricingModelMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputMarketEquityAdjustmentMember2022-09-300001280784htgc:MarchTwoThousandTwentySixANotesMember2022-01-012022-09-300001280784us-gaap:WarrantMemberus-gaap:MeasurementInputEbitdaMultipleMembersrt:MinimumMemberus-gaap:FairValueInputsLevel3Memberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:ReltioIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2022-01-012022-09-300001280784htgc:PineappleEnergyLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMember2021-12-310001280784htgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMemberhtgc:ElectronicsComputerHardwareMember2022-01-012022-09-300001280784us-gaap:EquitySecuritiesMembersrt:MaximumMemberus-gaap:MeasurementInputRevenueMultipleMemberus-gaap:FairValueInputsLevel3Memberhtgc:MarketComparableCompaniesMember2021-12-310001280784us-gaap:CommonStockMember2021-06-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMember2021-12-310001280784us-gaap:PrivateEquityFundsForeignMemberus-gaap:FairValueMeasurementsRecurringMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:RumbleONIncMember2022-01-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:AlbireoPharmaIncMember2021-01-012021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberus-gaap:CommonStockMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:DiversifiedFinancialServicesMemberhtgc:MajorityOwnedControlInvestmentsMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:SeriesAOnePreferredStockMemberhtgc:OfferUpIncMember2022-09-300001280784htgc:DebtInvestmentsMemberhtgc:ZimperiumIncMember2022-09-300001280784htgc:PineappleEnergyLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMember2021-01-012021-09-300001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMemberhtgc:MixpanelIncMember2021-12-310001280784htgc:EquityInvestmentsMemberhtgc:ElectronicsComputerHardwareMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:BicycleTherapeuticsPLCMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:ConvoyIncorporationMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:EvernoteCorporationMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2021-01-012021-12-310001280784htgc:ValoHealthLLCMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:SeriesBPreferredStockMember2022-01-012022-09-300001280784us-gaap:SalesRevenueNetMemberhtgc:InvestmentTypeConcentrationRiskMemberhtgc:InvestmentFundsAndVehiclesMember2021-01-012021-12-310001280784us-gaap:WarrantMemberhtgc:HealthcareServicesOtherMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:RocketPharmaceuticalsLtdMember2021-01-012021-12-310001280784us-gaap:CarryingReportedAmountFairValueDisclosureMemberhtgc:MarchTwoThousandTwentySixANotesMember2021-12-310001280784htgc:DebtInvestmentsMemberhtgc:CommunicationsAndNetworkingMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberhtgc:KaleidoBiosciencesIncMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784us-gaap:EquitySecuritiesMemberus-gaap:ValuationTechniqueOptionPricingModelMemberus-gaap:FairValueInputsLevel3Member2021-12-310001280784us-gaap:RevolvingCreditFacilityMember2022-01-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberhtgc:HibercellIncMemberus-gaap:SeriesBPreferredStockMember2022-09-300001280784htgc:DebtInvestmentMemberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784us-gaap:WarrantMemberus-gaap:MeasurementInputRevenueMultipleMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:LandingHoldingsIncMember2021-12-310001280784us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:BicycleTherapeuticsPLCMemberhtgc:ExitFeeMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:GeronCorporationMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:LyftIncMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:UnityBiotechnologyIncMember2022-09-300001280784us-gaap:MeasurementInputEbitdaMultipleMemberus-gaap:EquitySecuritiesMembersrt:MaximumMemberus-gaap:FairValueInputsLevel3Memberhtgc:MarketComparableCompaniesMember2021-12-310001280784htgc:AryakaNetworksIncMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:DebtInvestmentsUnderOneYearMaturityMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:GibraltarBusinessCapitalLLCMember2021-01-012021-09-300001280784htgc:PharmaceuticalsMembersrt:MinimumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMemberus-gaap:MeasurementInputDiscountRateMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:CampaignMonitorLimitedMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:CoriumIncMember2022-09-300001280784htgc:WarrantInvestmentMemberhtgc:ElectronicsComputerHardwareMember2022-09-300001280784us-gaap:FairValueInputsLevel3Memberus-gaap:UnsecuredDebtMemberus-gaap:FairValueMeasurementsRecurringMember2021-12-310001280784htgc:CoronadoAestheticsLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMember2022-01-012022-09-300001280784us-gaap:WarrantMemberhtgc:InternetConsumerAndBusinessServicesMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:RhinoLabsIncorporationMemberhtgc:SeriesBTwoPreferredStockMember2022-01-012022-09-300001280784us-gaap:WarrantMemberhtgc:ValuationTechniqueOtherMemberus-gaap:FairValueInputsLevel3Member2022-09-300001280784htgc:ImpossibleFoodsIncMemberhtgc:EquityInvestmentsMemberhtgc:SeriesEOnePreferredStockMemberhtgc:SustainableAndRenewableTechnologyMember2022-09-300001280784htgc:HerculesAdviserLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberus-gaap:MemberUnitsMemberhtgc:MajorityOwnedControlInvestmentsMember2021-01-012021-09-300001280784us-gaap:CommonStockMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:EnmarkSystemsIncorporationMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:ExpectedRealizableValueMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputHypotheticalMarketYieldMembersrt:WeightedAverageMemberhtgc:LowerMiddleMarketMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:ParatekPharmaceuticalsIncMember2021-12-310001280784htgc:AnnexCloudMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:EquityInvestmentsMemberus-gaap:SeriesAPreferredStockMemberhtgc:DiversifiedFinancialServicesMemberhtgc:GibraltarBusinessCapitalLLCMember2022-09-300001280784htgc:DelphixCorporationMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ScynexisIncMemberhtgc:ExitFeeMember2022-09-300001280784htgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Member2021-12-310001280784country:DE2021-12-310001280784htgc:HalioIncMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesBPreferredStockMemberhtgc:SustainableAndRenewableTechnologyMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:TecturaCorporationMember2021-01-012021-09-300001280784us-gaap:WarrantMembersrt:MaximumMemberus-gaap:ValuationTechniqueOptionPricingModelMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputMarketEquityAdjustmentMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberhtgc:DareBiosciencesIncMemberus-gaap:CommonStockMember2021-12-310001280784htgc:AgilenceIncorporationMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:FebruaryTwoThousandTwentyFiveNotesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:ThreeGTMSLLCMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784us-gaap:ManufacturingFacilityMember2022-09-300001280784htgc:DrugDeliveryMemberhtgc:WarrantInvestmentMemberhtgc:BioQPharmaIncorporatedMemberus-gaap:CommonStockMember2022-09-300001280784us-gaap:FairValueInputsLevel3Memberus-gaap:CommonStockMemberus-gaap:FairValueMeasurementsRecurringMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:CenturyTherapeuticsIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:MeasurementInputsProbabilityWeightingOfAlternativeOutcomesMemberhtgc:TechnologyMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMembersrt:WeightedAverageMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:SeniorsecuredtrancheaMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2021-01-012021-12-310001280784htgc:HerculesAdviserLLCMemberhtgc:UnsecuredDebtFivePercentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:DiversifiedFinancialServicesMember2021-12-310001280784htgc:NotesMember2018-09-240001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMember2021-01-012021-09-300001280784htgc:ModumetalIncMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:SustainableAndRenewableTechnologyMember2022-09-300001280784htgc:UnusedFacilityOtherFeesMemberhtgc:JanuaryTwoThousandTwentySevenNotesMember2022-01-012022-09-300001280784htgc:ConsumerAndBusinessProductsMember2022-09-300001280784htgc:DashlaneIncorporationMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2022-09-300001280784htgc:AlchemerLLCMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:InformationServicesMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:LyftIncMemberus-gaap:CommonStockMember2021-12-310001280784htgc:January2027NotesMember2022-01-202022-01-200001280784us-gaap:PreferredStockMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:MajorityOwnedControlInvestmentsMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:SioGeneTherapiesIncMember2022-01-012022-09-300001280784htgc:SMBCFacilityMember2022-01-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:SavaraIncMember2021-01-012021-12-310001280784htgc:UnrealizedGainLossMember2022-01-012022-09-300001280784htgc:SeriesTwoPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:SoftwareMemberhtgc:DruvaHoldingsIncMember2022-01-012022-09-300001280784htgc:AssetBackedNotesMemberus-gaap:VariableInterestEntityPrimaryBeneficiaryMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMember2022-09-300001280784htgc:MedicalDevicesMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMemberus-gaap:MeasurementInputDiscountRateMembersrt:WeightedAverageMember2022-09-300001280784htgc:EscrowReceivableMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2020-12-310001280784htgc:SBADebenturesMember2021-07-012021-09-300001280784us-gaap:EquitySecuritiesMemberus-gaap:ValuationTechniqueOptionPricingModelMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputMarketEquityAdjustmentMembersrt:WeightedAverageMember2022-09-300001280784us-gaap:SeriesAPreferredStockMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:DiversifiedFinancialServicesMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:MajorityOwnedControlInvestmentsMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:FulfilSolutionsIncMember2022-01-012022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:ContentfulGlobalIncMemberus-gaap:SeriesDPreferredStockMember2022-09-300001280784us-gaap:MeasurementInputDiscountForLackOfMarketabilityMemberus-gaap:EquitySecuritiesMembersrt:MaximumMemberhtgc:ValuationTechniqueLiquidationMemberus-gaap:FairValueInputsLevel3Member2021-12-310001280784us-gaap:MeasurementInputDiscountForLackOfMarketabilityMemberus-gaap:EquitySecuritiesMembersrt:MinimumMemberus-gaap:FairValueInputsLevel3Memberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:NineZeroEightDevicesIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:ElectronicsComputerHardwareMember2021-01-012021-12-310001280784htgc:SurgicalDevicesMemberhtgc:EquityInvestmentsMemberus-gaap:SeriesDPreferredStockMemberhtgc:GynesonicsIncMember2021-01-012021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:SeriesSeedPreferredStockMemberhtgc:BlackCrowAIIncMember2021-12-310001280784htgc:PerformanceVestingAwardsMember2021-09-300001280784us-gaap-supplement:InvestmentUnaffiliatedIssuerMember2022-09-300001280784htgc:MeasurementInputsProbabilityWeightingOfAlternativeOutcomesMembersrt:MaximumMemberhtgc:ExpectedRealizableValueMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:LowerMiddleMarketMember2021-12-310001280784us-gaap:SalesRevenueNetMemberhtgc:CollateralTypeConcentrationRiskMemberus-gaap:UnsecuredDebtMember2021-01-012021-12-310001280784htgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:DebtMaturingWithinOneYearMember2021-12-310001280784us-gaap:WarrantMemberus-gaap:MeasurementInputDiscountForLackOfMarketabilityMembersrt:MinimumMemberhtgc:ValuationTechniqueLiquidationMemberus-gaap:FairValueInputsLevel3Member2022-09-300001280784us-gaap:FairValueInputsLevel3Memberhtgc:MarchTwoThousandTwentySixANotesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2022-09-300001280784htgc:WarrantInvestmentMemberhtgc:SoftwareMemberhtgc:SeriesJuniorOnePreferredMemberhtgc:SignPostIncMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:CommunicationsAndNetworkingMemberhtgc:AryakaNetworksIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:ThreeGTMSLLCMemberhtgc:DebtInvestmentsMember2022-09-300001280784us-gaap:SeriesCPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:HealthcareServicesOtherMemberhtgc:CarbonHealthTechnologiesIncMember2021-01-012021-12-310001280784srt:MinimumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMemberus-gaap:MeasurementInputDiscountRateMemberhtgc:LowerMiddleMarketMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:ADMABiologicsIncMember2021-01-012021-12-310001280784htgc:CommunicationsAndNetworkingMemberhtgc:AryakaNetworksIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:MajorityOwnedControlInvestmentsMember2022-09-300001280784htgc:SurgicalDevicesMemberus-gaap:SeriesCPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:GynesonicsIncMember2021-12-310001280784htgc:SkydioIncorporationMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:WarrantInvestmentMemberhtgc:SeriesCOnePreferredStockMemberhtgc:ZeroFoxIncMemberhtgc:SoftwareMember2021-12-310001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:PoplicusIncMemberhtgc:SoftwareMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:BicycleTherapeuticsPLCMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMemberhtgc:LogicworksMember2021-12-310001280784htgc:ChemocentryxIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:EquityInvestmentsMemberus-gaap:SeriesAPreferredStockMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:DiversifiedFinancialServicesMember2021-01-012021-12-310001280784htgc:DebtInvestmentsMemberhtgc:SoftwareMember2021-12-310001280784htgc:LogicSourceMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:DrugDeliveryMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:PDSBiotechnologyCorporationMember2022-09-300001280784htgc:EquityInvestmentsMemberhtgc:DiversifiedFinancialServicesMember2021-12-310001280784htgc:ConsumerAndBusinessProductsMemberhtgc:TheNeatCompanyMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-09-3000012807842020-12-310001280784htgc:JuneTwoThousandTwentyFiveNotesMember2022-01-012022-09-300001280784us-gaap:FairValueInputsLevel2Memberus-gaap:EstimateOfFairValueFairValueDisclosureMemberhtgc:TwoThousandThirtyOneAssetBackedNotesMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:AffiliateInvestmentsMember2022-07-012022-09-300001280784us-gaap:WarrantMemberus-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:SeriesAOnePreferredStockMemberhtgc:OfferUpIncMember2022-01-012022-09-300001280784htgc:DebtInvestmentsMemberhtgc:IkonScienceLimitedMember2021-12-310001280784htgc:EquityInvestmentsMemberhtgc:HighRoadsIncMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMemberhtgc:ExitFeeMemberhtgc:UdacityIncMember2022-09-300001280784htgc:ConsumerAndBusinessProductsMemberhtgc:EquityInvestmentsMemberhtgc:TechStyleIncMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ThreatConnectIncMember2021-12-310001280784htgc:ValoHealthLLCMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:SeriesBPreferredStockMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:ConcertPharmaceuticalsIncMember2022-01-012022-09-300001280784htgc:WarrantInvestmentMemberhtgc:SeriesCOnePreferredStockMemberhtgc:SustainableAndRenewableTechnologyMemberhtgc:FulcrumBioenergyIncMember2021-12-310001280784us-gaap:FairValueInputsLevel3Memberus-gaap:CommonStockMemberus-gaap:FairValueMeasurementsRecurringMember2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:CommunicationsAndNetworkingMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:RocketLabGlobalServicesLLCMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:LocusBiosciencesIncMemberhtgc:ExitFeeMember2022-09-300001280784us-gaap:SeriesEPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:YipitLLCMemberhtgc:InformationServicesMember2022-09-300001280784htgc:OneTimeFeeMember2021-07-012021-09-300001280784htgc:CapitalInExcessOfParValueMember2022-07-012022-09-300001280784us-gaap:VariableInterestEntityPrimaryBeneficiaryMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:AveoPharmaceuticalsIncMember2022-09-300001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMemberhtgc:CouchbaseIncMember2021-12-310001280784us-gaap:EstimateOfFairValueFairValueDisclosureMember2021-12-310001280784htgc:SeniorSecuredDebtMember2021-12-310001280784htgc:YumanityTherapeuticsIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerMember2020-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:PreferredSeriesBBMemberhtgc:TecturaCorporationMember2022-01-012022-09-300001280784htgc:SurgicalDevicesMemberhtgc:SeriesFOnePreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:GynesonicsIncMember2021-12-310001280784htgc:HalioIncMemberhtgc:WarrantInvestmentMemberhtgc:SustainableAndRenewableTechnologyMember2022-09-300001280784htgc:OneMonthLIBORMember2021-12-310001280784htgc:SMBCFacilityMembersrt:MaximumMemberhtgc:ForeignCurrencyBorrowingMember2022-09-300001280784htgc:PineappleEnergyLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberus-gaap:CommonStockMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberus-gaap:PreferredStockMemberhtgc:BlackCrowAIIncMember2022-09-300001280784htgc:ImpossibleFoodsIncMemberhtgc:EquityInvestmentsMemberhtgc:SeriesEOnePreferredStockMemberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberus-gaap:SeriesCPreferredStockMemberhtgc:ShareThisIncMemberhtgc:WarrantInvestmentMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:NuvoloTechnologiesCorporationMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:GibraltarBusinessCapitalLLCMember2022-07-012022-09-300001280784htgc:MeasurementInputsProbabilityWeightingOfAlternativeOutcomesMembersrt:MaximumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMemberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:CarwowLimitedMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:BitsightTechnologiesIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2021-01-012021-12-310001280784us-gaap:WarrantMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2022-01-012022-09-300001280784htgc:UnsecuredDebtFourteenPointFiveZeroPercentageMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:DiversifiedFinancialServicesMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:MajorityOwnedControlInvestmentsMember2022-09-300001280784htgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMemberhtgc:DiversifiedFinancialServicesMember2021-01-012021-12-310001280784htgc:EquityInvestmentsMemberhtgc:CommonUnitsMemberhtgc:NantEnergyLLCMemberhtgc:SustainableAndRenewableTechnologyMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberus-gaap:CommonStockMemberhtgc:SolarSpectrumHoldingsLLCMember2021-09-300001280784htgc:TechnologyMembersrt:MinimumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMemberus-gaap:MeasurementInputDiscountRateMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:OtherControlInvestmentsMember2020-12-310001280784us-gaap:SeriesEPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:SingleStoreIncMemberhtgc:SoftwareMember2022-09-300001280784htgc:PineappleEnergyLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMember2022-01-012022-09-300001280784htgc:SeriesAAPreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:FlowonixMedicalIncorporatedMemberhtgc:MedicalDevicesAndEquipmentMember2022-09-300001280784htgc:MarchTwoThousandTwentySixBNotesMemberus-gaap:FairValueInputsLevel3Memberus-gaap:EstimateOfFairValueFairValueDisclosureMember2022-09-300001280784htgc:ConsumerAndBusinessProductsMemberhtgc:WarrantInvestmentMember2021-12-310001280784htgc:HerculesAdviserLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:DiversifiedFinancialServicesMemberhtgc:MajorityOwnedControlInvestmentsMemberus-gaap:UnsecuredDebtMember2021-01-012021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:GryphonNetworksCorporationMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:YumanityTherapeuticsIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:WellsFacilityMember2021-01-012021-09-300001280784htgc:DebtInvestmentsMemberhtgc:CarbonHealthTechnologiesIncMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:OfferUpIncMember2021-12-310001280784htgc:MeasurementInputsProbabilityWeightingOfAlternativeOutcomesMembersrt:MaximumMemberhtgc:ExpectedRealizableValueMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:HealthcareServicesOtherMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:CarbonHealthTechnologiesIncMemberhtgc:ExitFeeMember2022-09-300001280784htgc:TwoThousandThirtyOneAssetBackedNotesMember2022-01-012022-09-300001280784htgc:MeasurementInputsProbabilityWeightingOfAlternativeOutcomesMemberhtgc:TechnologyMembersrt:MaximumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMember2021-12-310001280784us-gaap:CarryingReportedAmountFairValueDisclosureMemberhtgc:SeptemberTwoThousandTwentySixNotesMember2021-12-310001280784htgc:PineappleEnergyLLCMemberhtgc:SeniorDebtMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMember2021-12-310001280784htgc:TechnologyMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMembersrt:WeightedAverageMemberus-gaap:MeasurementInputDiscountRateMember2021-12-310001280784htgc:IndustrySubSectorConcentrationRiskMemberhtgc:DrugDiscoveryAndDevelopmentMemberus-gaap:SalesRevenueNetMember2021-01-012021-12-310001280784us-gaap:PreferredStockMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2022-09-300001280784us-gaap:SeriesCPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:HealthcareServicesOtherMemberhtgc:CarbonHealthTechnologiesIncMember2022-01-012022-09-300001280784htgc:February2025NotesMember2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:ValoHealthLLCMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:EquityInvestmentsMemberhtgc:MedroboticsCorporationMemberus-gaap:SeriesGPreferredStockMemberhtgc:MedicalDevicesAndEquipmentMember2021-01-012021-12-310001280784us-gaap:SubsequentEventMemberhtgc:SupplementalDividendMember2022-11-170001280784htgc:TechnologyMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputHypotheticalMarketYieldMembersrt:WeightedAverageMemberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:JuneTwoThousandTwentyFiveNotesMember2022-09-300001280784us-gaap:RestrictedStockMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784srt:MinimumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputHypotheticalMarketYieldMemberhtgc:SustainableAndRenewableTechnologyMemberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:SeriesCOnePreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:SustainableAndRenewableTechnologyMemberhtgc:FulcrumBioenergyIncMember2022-01-012022-09-300001280784htgc:ConstructorIoCorporationMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:AxsomeTherapeuticsIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:BridgeBioPharmaIncMember2022-09-300001280784htgc:SurgicalDevicesMemberhtgc:EquityInvestmentsMemberus-gaap:SeriesBPreferredStockMemberhtgc:GynesonicsIncMember2022-09-300001280784htgc:MeasurementInputPremiumDiscountMembersrt:MaximumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MarketComparableCompaniesMemberhtgc:LowerMiddleMarketMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:BicycleTherapeuticsPLCMember2021-12-310001280784srt:MinimumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputHypotheticalMarketYieldMemberhtgc:MarketComparableCompaniesMemberhtgc:LowerMiddleMarketMember2021-12-310001280784htgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Member2022-09-300001280784htgc:MeasurementInputPremiumDiscountMemberhtgc:TechnologyMembersrt:MinimumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MarketComparableCompaniesMember2021-12-310001280784htgc:InvestmentFundsAndVehiclesMember2022-09-300001280784htgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMemberhtgc:CommunicationsAndNetworkingMember2021-01-012021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:ProventionBioIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:AcaciaPharmaIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:MUFGBankFacilityMemberhtgc:ThreeMonthSecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember2022-01-012022-09-300001280784htgc:WarrantInvestmentMemberhtgc:HalioIncPKKinestralTechnologiesIncMemberus-gaap:SeriesAPreferredStockMemberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:UberTechnologiesIncMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:SeriesAAPreferredStockMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:TheFactionGroupLLCMemberhtgc:WarrantInvestmentMember2021-01-012021-12-310001280784htgc:September2026NotesMember2022-01-012022-09-300001280784htgc:IncludedInCostMember2021-12-310001280784us-gaap:WarrantMemberhtgc:MediaContentInfoMember2022-09-300001280784htgc:UnusedFacilityOtherFeesMemberhtgc:TwoThousandThirtyThreeNotesMember2021-07-012021-09-300001280784htgc:ControlInvestmentsMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMember2022-01-012022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:BlackCrowAIIncMember2021-09-300001280784htgc:PineappleEnergyLLCMemberhtgc:SeniorDebtMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMember2021-01-012021-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:CopperCRMIncorporationMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DemandbaseIncorporationMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:AppDirectIncorporationMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:PharmaceuticalsMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MarketApproachValuationTechniqueMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:ContentfulGlobalIncMemberus-gaap:SeriesDPreferredStockMember2022-01-012022-09-300001280784htgc:March2026BNotesMember2022-09-300001280784htgc:HerculesCapitalFourLPMember2020-10-272020-10-270001280784us-gaap:WarrantMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2020-12-310001280784htgc:AprilTwoThousandTwentyFiveNotesMember2021-01-012021-09-300001280784us-gaap:GeographicConcentrationRiskMemberus-gaap:SalesRevenueNetMember2021-01-012021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:VideoAmpIncMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:CommunicationsAndNetworkingMemberhtgc:DebtInvestmentMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:CarwowLimitedMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784us-gaap:WarrantMemberhtgc:ConsumerAndBusinessProductsMember2022-09-300001280784htgc:SurgicalDevicesMemberhtgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMember2022-01-012022-09-300001280784htgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:DiversifiedFinancialServicesMember2021-12-310001280784htgc:SBADebenturesMember2021-01-012021-09-300001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:InformationServicesMemberhtgc:INMOBIIncMember2021-01-012021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesBPreferredStockMemberhtgc:CloudpayIncMember2022-01-012022-09-300001280784htgc:JulyTwoThousandTwentyFourNotesMemberhtgc:UnusedFacilityOtherFeesMember2022-01-012022-09-300001280784us-gaap:WarrantMemberhtgc:SustainableAndRenewableTechnologyMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:DermavantSciencesLtdMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:SeniorDebtMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberhtgc:BrickellBiotechIncMemberus-gaap:CommonStockMember2021-12-310001280784htgc:WarrantInvestmentMemberhtgc:HalioIncPKKinestralTechnologiesIncMemberus-gaap:SeriesBPreferredStockMemberhtgc:SustainableAndRenewableTechnologyMember2021-01-012021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:AriaSystemsIncMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesGPreferredStockMember2022-01-012022-09-300001280784htgc:TwoThousandThirtyThreeNotesMember2021-01-012021-09-300001280784htgc:SeriesCOnePreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:FulcrumBioenergyIncMemberhtgc:SustainableAndRenewableTechnologyMember2021-01-012021-12-310001280784htgc:SixMonthLIBORMember2022-09-300001280784htgc:InvestmentFundsVehiclesMemberhtgc:SoftwareMember2022-09-300001280784htgc:CommunicationsAndNetworkingMemberhtgc:AryakaNetworksIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-09-300001280784htgc:EquityInvestmentsMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:DiversifiedFinancialServicesMember2022-09-300001280784htgc:NabrivaTherapeuticsMemberhtgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsUnderOneYearMaturityMember2022-09-300001280784us-gaap:SubsequentEventMemberhtgc:SupplementalDividendMember2022-03-092022-10-130001280784htgc:HerculesAdviserLLCMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:DiversifiedFinancialServicesMemberus-gaap:UnsecuredDebtMember2022-09-300001280784htgc:DrugDeliveryMemberhtgc:EquityInvestmentsMemberhtgc:PDSBiotechnologyCorporationPKEdgeTherapeuticsIncMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784us-gaap:WarrantMemberus-gaap:MeasurementInputRevenueMultipleMemberus-gaap:ValuationTechniqueOptionPricingModelMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:LandingHoldingsIncMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:AnnexCloudMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMember2022-09-300001280784htgc:WarrantInvestmentMemberhtgc:SustainableAndRenewableTechnologyMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:LocusBiosciencesIncMember2022-09-300001280784htgc:MeasurementInputsProbabilityWeightingOfAlternativeOutcomesMemberhtgc:ExpectedRealizableValueMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:CerosIncorporationMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberus-gaap:CommonStockMemberhtgc:SolarSpectrumHoldingsLLCMember2020-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:OfferUpIncMemberus-gaap:SeriesAPreferredStockMember2021-12-310001280784htgc:G1TherapeuticsIncMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:SeriesOnePreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:InformationServicesMemberhtgc:NetBaseSolutionsIncMember2021-01-012021-12-310001280784htgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMemberhtgc:SustainableAndRenewableTechnologyMember2022-01-012022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberus-gaap:CommonStockMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2021-12-310001280784htgc:TwoThousandThirtyThreeNotesMember2022-09-300001280784htgc:MarchTwoThousandTwentySixANotesMember2021-07-012021-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:SolarSpectrumHoldingsLLCMember2021-09-300001280784htgc:SeniorSecuredDebtMemberus-gaap:InterestRateFloorMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:EnGeneIncMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:VeemIncorporationMemberhtgc:SeniorsecuredtranchebMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:SBADebenturesMember2022-09-300001280784htgc:EquityInvestmentsMemberhtgc:CommunicationsAndNetworkingMemberhtgc:PeerlessNetworkHoldingsIncMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:AutomationAnyWhereIncMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:BitsightTechnologiesIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2022-09-300001280784srt:MaximumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMemberus-gaap:MeasurementInputDiscountRateMemberhtgc:LowerMiddleMarketMember2022-09-300001280784htgc:EquityInvestmentsMemberus-gaap:SeriesDPreferredStockMemberhtgc:SustainableAndRenewableTechnologyMemberhtgc:PivotBioIncMember2021-01-012021-12-310001280784htgc:TarsusPharmaceuticalsIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2022-09-300001280784htgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:PlanetLabsIncMemberhtgc:InformationServicesMember2022-01-012022-09-300001280784srt:MaximumMemberhtgc:ExpectedRealizableValueMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputHypotheticalMarketYieldMemberhtgc:LowerMiddleMarketMember2021-12-310001280784us-gaap:CreditConcentrationRiskMember2022-09-300001280784htgc:ControlInvestmentsMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMember2022-07-012022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMember2021-07-012021-09-300001280784htgc:PerformanceVestingAwardsMember2022-09-300001280784us-gaap:WarrantMemberus-gaap:MeasurementInputDiscountForLackOfMarketabilityMembersrt:MaximumMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MarketApproachValuationTechniqueMember2022-09-300001280784htgc:EquityInvestmentsMemberhtgc:GelesisIncMemberus-gaap:CommonStockMemberhtgc:MedicalDevicesAndEquipmentMember2022-01-012022-09-300001280784us-gaap:FairValueInputsLevel2Memberus-gaap:CommonStockMemberus-gaap:FairValueMeasurementsRecurringMember2022-09-300001280784us-gaap:DebtMember2022-09-300001280784htgc:OusterIncorporationMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:AvaloTherapeuticsIncMember2022-01-012022-09-300001280784htgc:EvofemBiosciencesIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:CoronadoAestheticsLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberus-gaap:CommonStockMemberhtgc:MajorityOwnedControlInvestmentsMemberhtgc:MedicalDevicesAndEquipmentMember2021-12-310001280784htgc:HerculesCapitalFourLPMember2022-01-012022-09-300001280784htgc:ConsumerAndBusinessProductsMemberhtgc:EquityInvestmentsMemberhtgc:TechStyleIncMemberus-gaap:CommonStockMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784us-gaap:FairValueMeasurementsRecurringMember2021-12-310001280784htgc:MarchTwoThousandTwentySixBNotesMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:CutoverIncMember2022-09-300001280784htgc:EquityInvestmentsMemberhtgc:CommunicationsAndNetworkingMember2021-12-310001280784htgc:ZepzPKAWorldremitGroupLimitedMemberhtgc:InternetConsumerAndBusinessServicesMemberus-gaap:SeriesEPreferredStockMemberhtgc:WarrantInvestmentMember2021-12-310001280784htgc:SurgicalDevicesMemberhtgc:WarrantInvestmentMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:BiomXINCMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:UniQureBVMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:SupplementalDividendMember2022-03-090001280784htgc:DrugDeliveryMemberhtgc:AeramiTherapeuticsHoldingsIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMember2020-12-310001280784us-gaap:WarrantMemberus-gaap:MeasurementInputRevenueMultipleMembersrt:MinimumMemberus-gaap:FairValueInputsLevel3Memberhtgc:MarketComparableCompaniesMember2021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:AffiliateInvestmentsMember2021-01-012021-09-300001280784htgc:RapidMinerIncMemberhtgc:SeriesCOnePreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:SoftwareMember2021-12-310001280784htgc:SeriesAAPreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:FlowonixMedicalIncorporatedMemberhtgc:MedicalDevicesAndEquipmentMember2022-01-012022-09-300001280784htgc:PineappleEnergyLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:SeniorsecuredtranchebMemberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784htgc:EquityInvestmentsMemberhtgc:SeriesThreePreferredStockMemberhtgc:SoftwareMemberhtgc:DruvaHoldingsIncMember2022-01-012022-09-300001280784htgc:EquityInvestmentsMemberhtgc:SoftwareMember2021-12-310001280784htgc:LightbendIncMemberhtgc:WarrantInvestmentMemberhtgc:SoftwareMemberus-gaap:SeriesDPreferredStockMember2021-01-012021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:OfferUpIncMemberus-gaap:SeriesAPreferredStockMember2021-01-012021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:CenturyTherapeuticsIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-09-300001280784us-gaap:WarrantMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2021-01-012021-09-300001280784htgc:JuneTwoThousandTwentyFiveNotesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2022-09-300001280784us-gaap:SalesRevenueNetMemberhtgc:CollateralTypeConcentrationRiskMemberhtgc:SecondLienMember2021-01-012021-12-310001280784htgc:ExitFeesAmortizationMember2021-01-012021-09-300001280784htgc:PineappleEnergyLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMember2021-09-300001280784us-gaap:CarryingReportedAmountFairValueDisclosureMemberhtgc:TwoThousandThirtyOneAssetBackedNotesMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:AtaiLifeSciencesNVMember2022-09-300001280784us-gaap:WarrantMembersrt:MinimumMemberus-gaap:ValuationTechniqueOptionPricingModelMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputMarketEquityAdjustmentMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:ParatekPharmaceuticalsIncMember2021-01-012021-12-310001280784htgc:FebruaryTwoThousandTwentyFiveNotesMemberhtgc:UnusedFacilityOtherFeesMember2021-07-012021-09-300001280784us-gaap:WarrantMemberus-gaap:MeasurementInputRevenueMultipleMembersrt:MaximumMemberhtgc:ValuationTechniqueLiquidationMemberus-gaap:FairValueInputsLevel3Member2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsMember2022-09-300001280784us-gaap:SeriesEPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:YipitLLCMemberhtgc:InformationServicesMember2022-01-012022-09-300001280784us-gaap:EquitySecuritiesMemberhtgc:ValuationTechniqueOtherMemberus-gaap:FairValueInputsLevel3Member2021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:BlackCrowAIIncMember2022-07-012022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:TecturaCorporationMember2021-01-012021-12-310001280784htgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMemberhtgc:MedicalDevicesAndEquipmentMember2022-01-012022-09-300001280784htgc:RivieraPartnersLLCMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:TwoThousandTwentyEightAssetBackedNotesMemberhtgc:UnusedFacilityOtherFeesMember2021-01-012021-09-300001280784htgc:EigenTechnologiesLimitedMemberhtgc:SeniorSecuredDebtMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMemberhtgc:ExitFeeMember2022-09-300001280784htgc:EnmarkSystemsIncorporationMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:SBADebenturesIssuedOnDecemberTwentyEightTwoThousandAndTwentyOneMember2022-09-300001280784htgc:TechnologyMemberhtgc:ValuationTechniqueLiquidationMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Member2022-09-300001280784htgc:DispatchTechnologiesIncMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:InvestmentFundsVehiclesMemberhtgc:ForbionGrowthOpportunitiesFundIICVMember2022-01-012022-09-300001280784us-gaap:WarrantMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2021-09-300001280784us-gaap:PreferredStockMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:BlackCrowAIIncMember2021-09-300001280784htgc:DebtInvestmentsMemberhtgc:ManufacturingTechnologyMember2021-12-310001280784htgc:March2026BNotesMember2021-03-042021-03-040001280784htgc:EquityInvestmentsMemberhtgc:SeriesTwoPreferredStockMemberhtgc:SoftwareMemberhtgc:DruvaHoldingsIncMember2021-01-012021-12-310001280784htgc:TechnologyMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MarketApproachValuationTechniqueMember2022-09-300001280784htgc:JuneTwoThousandTwentyFiveThreeYearNotesMemberhtgc:UnusedFacilityOtherFeesMember2022-01-012022-09-300001280784htgc:GelesisIncMemberhtgc:SeriesAOnePreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:MedicalDevicesAndEquipmentMember2021-12-310001280784htgc:SingleStoreIncMemberhtgc:WarrantInvestmentMemberhtgc:SoftwareMemberus-gaap:SeriesDPreferredStockMember2022-09-300001280784htgc:UnusedFacilityOtherFeesMemberhtgc:MarchTwoThousandTwentySixANotesMember2022-01-012022-09-300001280784htgc:AmpionPBCMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SustainableAndRenewableTechnologyMember2022-09-300001280784us-gaap:MeasurementInputDiscountForLackOfMarketabilityMemberus-gaap:EquitySecuritiesMembersrt:MaximumMemberhtgc:ValuationTechniqueLiquidationMemberus-gaap:FairValueInputsLevel3Member2022-09-300001280784us-gaap:FairValueInputsLevel3Memberhtgc:JuneTwoThousandTwentyFiveThreeYearNotesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2022-09-300001280784htgc:EquityInvestmentsMemberhtgc:MedroboticsCorporationMemberus-gaap:SeriesGPreferredStockMemberhtgc:MedicalDevicesAndEquipmentMember2021-12-310001280784htgc:JulyTwoThousandTwentyFourNotesMemberhtgc:UnusedFacilityOtherFeesMember2022-07-012022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:TecturaCorporationMember2022-09-300001280784htgc:HalioIncMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesAPreferredStockMemberhtgc:SustainableAndRenewableTechnologyMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:HibercellIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:ConvoyIncorporationMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:SMBCFacilityMemberus-gaap:FairValueInputsLevel3Memberus-gaap:EstimateOfFairValueFairValueDisclosureMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WorldremitGroupLimitedMemberhtgc:WarrantInvestmentMember2022-09-300001280784htgc:ConsumerAndBusinessProductsMemberhtgc:WarrantInvestmentMemberhtgc:TechStyleIncPKJustFabulousIncMemberus-gaap:SeriesBPreferredStockMember2021-12-310001280784htgc:PineappleEnergyLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberus-gaap:CommonStockMember2020-12-310001280784htgc:HerculesCapitalFourLPMember2022-09-300001280784htgc:ThreeGTMSLLCMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:MajorityOwnedControlInvestmentsMember2021-09-300001280784htgc:EscrowReceivableMemberus-gaap:FairValueMeasurementsRecurringMember2021-12-310001280784srt:MaximumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMemberus-gaap:MeasurementInputDiscountRateMemberhtgc:LowerMiddleMarketMember2021-12-310001280784htgc:DebtInvestmentsMemberhtgc:CytracomHoldingsLLCMember2021-12-310001280784htgc:ZoomMediaGroupIncMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesAPreferredStockMemberhtgc:MediaContentInfoMember2021-01-012021-12-310001280784htgc:NewfrontInsuranceHoldingsIncMemberhtgc:EquityInvestmentsMemberhtgc:SeriesDTwoPreferredStockMemberhtgc:DiversifiedFinancialServicesMember2022-01-012022-09-300001280784htgc:AgilenceIncorporationMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:SoftwareMemberhtgc:DockerIncMember2022-01-012022-09-300001280784htgc:TwoThousandTwentyTwoNotesMember2021-12-310001280784htgc:DrugDeliveryMemberhtgc:EquityInvestmentsMember2021-12-310001280784htgc:TwoThousandTwentyTwoEquityDistributionAgreementMember2022-07-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:ConcertPharmaceuticalsIncMember2021-12-310001280784htgc:MarketYieldAnalysisMemberhtgc:PharmaceuticalsMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Member2021-12-310001280784htgc:SBADebenturesIssuedOnDecemberTwentyThreeTwoThousandAndTwentyOneMember2022-09-300001280784htgc:AspireBariatricsIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:MedicalDevicesAndEquipmentMember2022-01-012022-09-300001280784htgc:SeniorDebtMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:SolarSpectrumHoldingsLLCMember2020-12-310001280784htgc:AytuBioScienceIncMemberhtgc:DrugDeliveryMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:TarsusPharmaceuticalsIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:WarrantInvestmentMemberhtgc:DemandbaseIncorporationMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2022-09-300001280784htgc:June20253YearNotesMember2022-09-300001280784htgc:DrugDeliveryMemberhtgc:EquityInvestmentsMemberhtgc:AcelRxPharmaceuticalsIncMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784country:IEus-gaap:GeographicConcentrationRiskMemberus-gaap:SalesRevenueNetMember2022-01-012022-09-300001280784htgc:FebruaryTwoThousandTwentyFiveNotesMember2021-01-012021-09-300001280784htgc:FebruaryTwoThousandTwentyFiveNotesMemberhtgc:UnusedFacilityOtherFeesMember2022-07-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMemberhtgc:EsmeLearningSolutionsIncorporationMemberhtgc:ExitFeeMember2022-09-300001280784htgc:SeniorSecuredDebtMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2022-01-012022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberus-gaap:CommonStockMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2022-01-012022-09-300001280784htgc:DrugDeliveryMemberhtgc:AeramiTherapeuticsHoldingsIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-12-310001280784us-gaap:FairValueInputsLevel3Memberus-gaap:UnsecuredDebtMemberus-gaap:FairValueMeasurementsRecurringMember2022-01-012022-09-300001280784htgc:AkeroTherapeuticsIncMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:PikMember2021-07-012021-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMember2021-12-310001280784htgc:InvestmentFundsVehiclesMember2022-09-300001280784htgc:SingleStoreIncMemberhtgc:WarrantInvestmentMemberhtgc:SoftwareMemberus-gaap:SeriesDPreferredStockMember2021-01-012021-12-310001280784htgc:EquityInvestmentsMemberhtgc:MedicalDevicesAndEquipmentMember2022-09-300001280784htgc:FebruaryTwoThousandTwentyFiveNotesMember2021-12-310001280784htgc:WarrantInvestmentMemberus-gaap:SeriesDPreferredStockMemberhtgc:SustainableAndRenewableTechnologyMember2021-01-012021-12-310001280784htgc:EvofemBiosciencesIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-12-310001280784htgc:TactAiTechnologiesIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2022-09-300001280784htgc:SMBCFacilityMember2022-01-012022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:SnagajobcomIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:DiversifiedFinancialServicesMember2022-09-300001280784us-gaap:RestrictedStockMember2022-07-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:ScynexisIncMember2021-01-012021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberus-gaap:SeriesCPreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:LogicSourceMember2021-01-012021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:CellarityIncMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesBPreferredStockMember2021-12-310001280784htgc:DebtInvestmentMemberhtgc:InformationServicesMember2021-12-310001280784htgc:UnsecuredDebtFourteenPointFiveZeroPercentageMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:DiversifiedFinancialServicesMemberhtgc:GibraltarBusinessCapitalLLCMember2021-12-310001280784htgc:HerculesAdviserLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMember2021-07-012021-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:WorldremitGroupLimitedMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:MajorityOwnedControlInvestmentsMember2021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberus-gaap:CommonStockMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2021-01-012021-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMember2022-01-012022-09-300001280784us-gaap:EquitySecuritiesMemberus-gaap:MeasurementInputRevenueMultipleMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:NextrollIncorporationMemberhtgc:DebtInvestmentsUnderOneYearMaturityMember2022-09-300001280784htgc:ZepzPKAWorldremitGroupLimitedMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesDPreferredStockMember2021-12-310001280784htgc:FebruaryTwoThousandTwentyFiveNotesMember2022-01-012022-09-300001280784htgc:TwoThousandThirtyThreeNotesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2021-12-310001280784us-gaap:PrivateEquityFundsForeignMemberus-gaap:FairValueMeasurementsRecurringMember2022-09-300001280784htgc:DashlaneIncorporationMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2021-01-012021-12-310001280784us-gaap:SeriesCPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:HealthcareServicesOtherMemberhtgc:CarbonHealthTechnologiesIncMember2022-09-300001280784htgc:TwoThousandTwentyTwoNotesMember2021-01-012021-09-300001280784us-gaap:SeriesCPreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:DNAnexusIncMemberhtgc:SoftwareMember2022-01-012022-09-300001280784us-gaap:WarrantMemberhtgc:MedicalDevicesAndEquipmentMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:G1TherapeuticsIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:ThumbtackIncorporationMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:JulyTwoThousandTwentyFourNotesMember2021-01-012021-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMember2021-12-310001280784htgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:UnsecuredDebtElevenPointFiveZeroPercentageMemberhtgc:DiversifiedFinancialServicesMember2021-12-310001280784htgc:SeniorSecuredDebtMemberus-gaap:FairValueMeasurementsRecurringMember2022-09-300001280784htgc:SeriesTwoPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:SoftwareMemberhtgc:DruvaHoldingsIncMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ZimperiumIncMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMember2021-07-012021-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:NextdoorComIncMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:UnrealizedGainLossMember2021-01-012021-09-300001280784us-gaap:FairValueInputsLevel3Memberus-gaap:DebtMemberhtgc:AppreciationMember2021-01-012021-09-300001280784htgc:CommunicationsAndNetworkingMemberhtgc:SpringMobileSolutionsIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-12-310001280784htgc:SBADebenturesIssuedOnJulyTwentyEightTwoThousandAndTwentyOneMember2022-01-012022-09-300001280784htgc:OusterIncorporationMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:SemiconductorsMemberus-gaap:SeriesCPreferredStockMemberhtgc:AchronixSemiconductorCorporationMemberhtgc:EquityInvestmentsMember2021-01-012021-12-310001280784us-gaap:CommonStockMemberhtgc:TwoThousandTwentyEquityDistributionAgreementMember2022-01-012022-09-300001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMemberhtgc:ZimperiumIncMember2021-01-012021-12-310001280784htgc:MUFGBankFacilityMemberhtgc:LenderMember2021-12-310001280784htgc:TwoThousandTwentyTwoConvertibleNotesMemberhtgc:UnusedFacilityOtherFeesMember2022-07-012022-09-300001280784htgc:SemiconductorsMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:FungibleIncorporationMember2022-01-012022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:OportunMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:ForbionGrowthOpportunitiesFundICVMemberhtgc:InvestmentFundsAndVehiclesMember2021-01-012021-12-310001280784htgc:EquityInvestmentsMemberhtgc:HealthcareServicesOtherMemberhtgc:TwentyThreeAndMeIncMemberus-gaap:CommonStockMember2022-09-300001280784htgc:TwoThousandTwentyEightAssetBackedNotesMember2021-01-012021-09-300001280784us-gaap:SeriesEPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:SkydioIncorporationMemberhtgc:ElectronicsComputerHardwareMember2022-01-012022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:SeniorsecuredtranchebMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:TecturaCorporationMember2021-12-310001280784htgc:PineappleEnergyLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberus-gaap:CommonStockMember2021-09-300001280784htgc:SurgicalDevicesMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:TransMedicsGroupIncPKTransmedicsIncMember2022-09-300001280784htgc:SingleStoreIncMemberhtgc:WarrantInvestmentMemberhtgc:SoftwareMemberus-gaap:SeriesDPreferredStockMember2021-12-310001280784htgc:TwoThousandThirtyOneAssetBackedNotesMember2022-07-012022-09-300001280784htgc:BrainCorporationMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2022-01-012022-09-300001280784htgc:UnusedFacilityOtherFeesMemberhtgc:MarchTwoThousandTwentySixANotesMember2021-01-012021-09-300001280784us-gaap:MeasurementInputEbitdaMultipleMemberus-gaap:EquitySecuritiesMembersrt:MinimumMemberus-gaap:FairValueInputsLevel3Memberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:ZoomMediaGroupIncMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesAPreferredStockMemberhtgc:MediaContentInfoMember2021-12-310001280784htgc:SurgicalDevicesMemberus-gaap:SeriesCPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:GynesonicsIncMember2022-09-300001280784htgc:WarrantInvestmentMemberhtgc:MedicalDevicesAndEquipmentMember2021-12-310001280784htgc:SoftwareMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberus-gaap:SeriesCPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:ContentfulGlobalIncMember2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:CapRateMemberhtgc:GritstoneBioIncMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:RhinoLabsIncorporationMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:HealthcareServicesOtherMemberhtgc:DebtInvestmentMember2022-09-300001280784htgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:PlanetLabsIncMemberhtgc:InformationServicesMember2021-01-012021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:SeniorDebtMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2022-09-300001280784htgc:SBADebenturesIssuedOnDecemberTwentyEightTwoThousandAndTwentyOneMember2022-01-012022-09-300001280784htgc:TwoThousandTwentySevenAssetBackedNotesMember2021-01-012021-09-300001280784htgc:EscrowReceivableMemberus-gaap:FairValueMeasurementsRecurringMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:TecturaCorporationMember2021-12-310001280784htgc:AprilTwoThousandTwentyFiveNotesMember2021-07-012021-09-300001280784htgc:MeasurementInputPremiumDiscountMembersrt:MaximumMemberhtgc:ExpectedRealizableValueMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:LowerMiddleMarketMember2021-12-310001280784htgc:InformationServicesMember2022-09-300001280784us-gaap:CommonStockMember2021-07-012021-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:SeriesThreeClassCPreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:EnGeneIncMember2021-12-310001280784us-gaap:SalesRevenueNetMemberhtgc:FirstLienLastOutSeniorSecuredMemberhtgc:CollateralTypeConcentrationRiskMember2022-01-012022-09-300001280784htgc:InvestmentFundsAndVehiclesMember2021-12-310001280784country:IL2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:AlbireoPharmaIncMember2021-01-012021-12-310001280784us-gaap:ValuationTechniqueDiscountedCashFlowMemberus-gaap:EquitySecuritiesMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberus-gaap:MeasurementInputDiscountRateMember2021-12-310001280784htgc:ReischlingPressIncMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2021-12-310001280784us-gaap:EquitySecuritiesMembersrt:MaximumMemberus-gaap:ValuationTechniqueOptionPricingModelMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputMarketEquityAdjustmentMember2021-12-310001280784htgc:DrugDeliveryMemberhtgc:WarrantInvestmentMemberhtgc:BioQPharmaIncorporatedMemberus-gaap:CommonStockMember2021-12-310001280784htgc:CloudianIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2022-01-012022-09-300001280784htgc:DrugDeliveryMemberhtgc:EquityInvestmentsMemberhtgc:BioQPharmaIncorporatedMemberus-gaap:SeriesDPreferredStockMember2021-01-012021-12-310001280784htgc:SoftwareMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:ScynexisIncMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:SeniorsecuredtranchecMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2022-01-012022-09-300001280784htgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:SprinklrIncMemberhtgc:SoftwareMember2022-01-012022-09-300001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMemberhtgc:CloudBoltSoftwareIncorporationMember2022-01-012022-09-300001280784htgc:OtherMemberus-gaap:GeographicConcentrationRiskMemberus-gaap:SalesRevenueNetMember2021-01-012021-12-310001280784htgc:DebtInvestmentsMemberhtgc:DiversifiedFinancialServicesMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:EsmeLearningSolutionsIncorporationMember2022-09-300001280784us-gaap:FairValueInputsLevel3Memberhtgc:MarchTwoThousandTwentySixANotesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2021-12-310001280784htgc:SurgicalDevicesMemberhtgc:EquityInvestmentsMemberhtgc:GynesonicsIncMember2022-09-300001280784htgc:SeptemberTwoThousandTwentySixNotesMember2022-01-012022-09-300001280784htgc:OtherMember2021-12-310001280784htgc:ThreeMonthLIBORMember2022-09-300001280784us-gaap:PreferredStockMemberus-gaap:SalesRevenueNetMemberhtgc:InvestmentTypeConcentrationRiskMember2021-01-012021-12-310001280784htgc:LightbendIncMemberhtgc:WarrantInvestmentMemberhtgc:SoftwareMemberus-gaap:SeriesDPreferredStockMember2021-12-310001280784htgc:SBADebenturesIssuedOnAugustTwentyTwoThousandAndTwentyOneMember2022-01-012022-09-300001280784htgc:DrugDeliveryMember2021-12-310001280784us-gaap:SubsequentEventMemberhtgc:BaseDividendMember2022-11-172022-11-170001280784us-gaap-supplement:InvestmentAffiliatedIssuerMemberhtgc:ControlAndAffiliateInvestmentsMember2022-07-012022-09-300001280784htgc:HerculesAdviserLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:MajorityOwnedControlInvestmentsMemberus-gaap:UnsecuredDebtMember2021-01-012021-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:SeriesAOnePreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:OfferUpIncMember2021-01-012021-12-310001280784us-gaap:EquitySecuritiesMemberus-gaap:ValuationTechniqueOptionPricingModelMemberus-gaap:FairValueInputsLevel3Member2022-09-300001280784htgc:SMBCFacilityMember2021-12-310001280784country:GB2022-09-300001280784htgc:TwoThousandTwentyTwoEquityDistributionAgreementMemberus-gaap:CommonStockMember2022-07-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:HealthcareServicesOtherMemberhtgc:BlueSprigPediatricsIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:CenturyTherapeuticsIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-12-310001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:OutsetMedicalIncMemberhtgc:MedicalDevicesAndEquipmentMember2021-01-012021-12-310001280784us-gaap:SeriesEPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:SoftwareMemberhtgc:VeranaHealthIncMember2021-12-310001280784htgc:SixPointTwoFiveNotesDueTwoThousandThirtyThreeMember2022-01-012022-09-300001280784htgc:DebtInvestmentsMemberhtgc:GritstoneBioIncMember2021-12-310001280784htgc:MUFGBankFacilityMember2022-01-012022-09-300001280784htgc:ElationHealthIncMemberhtgc:HealthcareServicesOtherMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-09-300001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:InformationServicesMemberhtgc:INMOBIIncMember2021-12-310001280784htgc:BlueSprigPediatricsIncMemberhtgc:DebtInvestmentsMember2022-09-300001280784us-gaap:SeriesFPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:SingleStoreIncMemberhtgc:SoftwareMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:RivieraPartnersLLCMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMember2022-09-300001280784htgc:DrugDeliveryMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:PDSBiotechnologyCorporationMember2022-01-012022-09-300001280784htgc:EquityInvestmentsMemberhtgc:InformationServicesMember2021-12-310001280784htgc:TactAiTechnologiesIncMemberhtgc:SeniorSecuredDebtMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:CommunicationsAndNetworkingMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:CytracomHoldingsLLCMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:TecturaCorporationMember2022-09-300001280784htgc:JanuaryTwoThousandTwentySevenNotesMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:AlbireoPharmaIncMember2022-01-012022-09-300001280784htgc:HerculesAdviserLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:DiversifiedFinancialServicesMemberus-gaap:UnsecuredDebtMemberhtgc:MajorityOwnedControlInvestmentsMember2021-12-310001280784us-gaap:ConvertibleDebtMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:BlackCrowAIIncMember2021-01-012021-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberus-gaap:CommonStockMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:MajorityOwnedControlInvestmentsMember2021-01-012021-09-300001280784htgc:September2026NotesMember2021-09-160001280784htgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMemberhtgc:InformationServicesMember2021-01-012021-12-310001280784us-gaap:WarrantMemberus-gaap:FairValueInputsLevel1Member2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:EqualityHealthLLCMemberhtgc:HealthcareServicesOtherMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:SbaFacilityFeeMemberhtgc:HerculesCapitalFourLPMember2022-09-300001280784htgc:PrepaymentFeesMember2022-02-222022-02-220001280784htgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMemberhtgc:SoftwareMember2021-01-012021-12-310001280784htgc:MeasurementInputsProbabilityWeightingOfAlternativeOutcomesMembersrt:MinimumMemberhtgc:ValuationTechniqueLiquidationMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:LowerMiddleMarketMember2021-12-310001280784us-gaap:SalesRevenueNetMemberhtgc:SecondLienMemberhtgc:CollateralTypeConcentrationRiskMember2022-01-012022-09-300001280784htgc:CommunicationsAndNetworkingMemberhtgc:DebtInvestmentMember2022-09-300001280784us-gaap:PreferredStockMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:MajorityOwnedControlInvestmentsMember2021-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:LuciraHealthIncorporationMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:MedicalDevicesAndEquipmentMemberhtgc:ExitFeeMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:ViridianTherapeuticsIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:CapRateMember2022-09-300001280784htgc:TactAiTechnologiesIncMemberhtgc:SeniorSecuredDebtMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:AxsomeTherapeuticsIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:AtaiLifeSciencesNVMemberhtgc:ExitFeeMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerMemberhtgc:ControlAndAffiliateInvestmentsMember2022-01-012022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberhtgc:LendioIncMemberus-gaap:SeriesDPreferredStockMember2021-12-310001280784us-gaap:EquitySecuritiesMembersrt:MaximumMemberus-gaap:MeasurementInputRevenueMultipleMemberhtgc:ValuationTechniqueLiquidationMemberus-gaap:FairValueInputsLevel3Member2021-12-310001280784us-gaap-supplement:InvestmentUnaffiliatedIssuerMember2021-07-012021-09-300001280784htgc:AxsomeTherapeuticsIncMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:HerculesAdviserLLCMemberus-gaap:MemberUnitsMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:MajorityOwnedControlInvestmentsMember2022-09-300001280784htgc:PineappleEnergyLLCMemberhtgc:DebtInvestmentsUnderOneYearMaturityMemberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784us-gaap:DebtMember2021-12-310001280784htgc:SBADebenturesIssuedOnMarchTwentySixTwoThousandAndTwentyOneMember2022-01-012022-09-300001280784htgc:TechnologyMemberhtgc:MarketYieldAnalysisMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Member2021-12-310001280784htgc:ConsumerAndBusinessProductsMemberhtgc:PenumbraBrandsLLCMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:SoftwareMemberhtgc:DebtInvestmentsUnderOneYearMaturityMember2022-09-300001280784htgc:ConsumerAndBusinessProductsMemberus-gaap:SeriesCPreferredStockMemberhtgc:WhoopIncMemberhtgc:WarrantInvestmentMember2022-09-300001280784htgc:OmedaHoldingsLlcMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:OusterIncorporationMemberhtgc:ManufacturingTechnologyMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784us-gaap:UnsecuredDebtMember2021-12-310001280784htgc:SeniorSecuredDebtMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2021-01-012021-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:SeatGeekIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMemberhtgc:CapRateMemberhtgc:CopperCRMIncorporationMember2022-09-300001280784htgc:FebruaryTwoThousandTwentyFiveNotesMember2022-09-300001280784htgc:ExcludingCashAndCashEquivalentMemberus-gaap:FairValueMeasurementsRecurringMember2021-12-310001280784htgc:EscrowReceivableMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2022-01-012022-09-300001280784us-gaap:MeasurementInputDiscountForLackOfMarketabilityMemberus-gaap:EquitySecuritiesMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberhtgc:MarketComparableCompaniesMember2021-12-310001280784htgc:DebtInvestmentsMemberhtgc:DiversifiedFinancialServicesMember2021-12-310001280784us-gaap:PreferredStockMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:BlackCrowAIIncMember2020-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:OtherControlInvestmentsMember2022-09-300001280784htgc:March2026BNotesMember2022-01-012022-09-300001280784htgc:IvericBioGeneTherapyLlcMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:NewfrontInsuranceHoldingsIncMemberhtgc:EquityInvestmentsMemberhtgc:SeriesDTwoPreferredStockMemberhtgc:DiversifiedFinancialServicesMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DebtInvestmentsGreaterThanFiveYearsMaturityMemberhtgc:SoftwareMemberhtgc:AlchemerLLCMember2022-09-300001280784htgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:DiversifiedFinancialServicesMemberhtgc:GibraltarBusinessCapitalLLCMember2022-01-012022-09-300001280784us-gaap:CommonStockMember2022-07-012022-09-300001280784htgc:UnsecuredDebtFourteenPointFiveZeroPercentageMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:DiversifiedFinancialServicesMemberhtgc:MajorityOwnedControlInvestmentsMember2022-01-012022-09-300001280784htgc:EquityInvestmentsMemberus-gaap:SeriesDPreferredStockMemberhtgc:SustainableAndRenewableTechnologyMemberhtgc:PivotBioIncMember2022-01-012022-09-300001280784htgc:TechnologyMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMember2021-12-310001280784htgc:MedicalDevicesMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:SeniorsecuredtrancheaMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:TecturaCorporationMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:TFGHoldingIncMember2021-01-012021-12-310001280784htgc:SemiconductorsMemberhtgc:AchronixSemiconductorCorporationMemberhtgc:WarrantInvestmentMemberhtgc:SeriesDTwoPreferredStockMember2021-12-310001280784htgc:MUFGBankFacilityMemberus-gaap:CarryingReportedAmountFairValueDisclosureMember2022-09-300001280784htgc:EquityInvestmentsMemberhtgc:CommonUnitsMemberhtgc:CoronadoAestheticsLLCMemberhtgc:MedicalDevicesAndEquipmentMember2021-12-310001280784htgc:HerculesAdviserLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberus-gaap:UnsecuredDebtMemberhtgc:MajorityOwnedControlInvestmentsMember2021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:DiversifiedFinancialServicesMemberhtgc:UnsecuredDebtElevenPointFiveZeroPercentageMemberhtgc:MajorityOwnedControlInvestmentsMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:CarwowLimitedMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:SBADebenturesIssuedOnJuneTwentyFiveTwoThousandAndTwentyOneMember2022-01-012022-09-300001280784htgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMemberhtgc:HealthcareServicesOtherMember2022-01-012022-09-300001280784htgc:MarchTwoThousandTwentySixBNotesMember2021-07-012021-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:InvestmentFundsVehiclesMemberhtgc:ForbionGrowthOpportunitiesFundIICVMember2022-09-300001280784htgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:SoftwareMemberhtgc:DockerIncMember2021-12-310001280784htgc:ManufacturingTechnologyMemberhtgc:DebtInvestmentsUnderOneYearMaturityMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:AlbireoPharmaIncMember2021-12-310001280784htgc:EquityInvestmentsMemberhtgc:PlanetLabsIncMemberus-gaap:CommonStockMemberhtgc:InformationServicesMember2021-12-310001280784htgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:DiversifiedFinancialServicesMemberhtgc:GibraltarBusinessCapitalLLCMember2021-12-310001280784us-gaap:WarrantMemberus-gaap:SalesRevenueNetMemberhtgc:InvestmentTypeConcentrationRiskMember2021-01-012021-12-310001280784htgc:SeriesAAPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:FlowonixMedicalIncorporatedMemberhtgc:MedicalDevicesAndEquipmentMember2021-12-310001280784us-gaap:FairValueInputsLevel3Memberhtgc:JanuaryTwoThousandTwentySevenNotesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2022-09-300001280784htgc:LogicSourceMemberhtgc:DebtInvestmentsMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:TecturaCorporationMember2022-07-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:AppliedGeneticTechnologiesCorporationMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:ContentfulGlobalIncMemberus-gaap:SeriesDPreferredStockMember2021-12-310001280784htgc:LeaseAndLicenseObligationsMember2022-09-300001280784us-gaap:CommonStockMember2021-07-012021-09-300001280784htgc:EquityAndWarrantInvestmentsMemberus-gaap:FairValueInputsLevel3Member2022-09-300001280784htgc:PerformanceVestingAwardsMember2021-01-012021-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:CapRateMemberhtgc:BicycleTherapeuticsPLCMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:PreferredSeriesBBMemberhtgc:TecturaCorporationMember2021-12-310001280784htgc:SemiconductorsMemberhtgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMember2022-01-012022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:AffiliateInvestmentsMember2021-07-012021-09-300001280784htgc:SeriesOnePreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:InformationServicesMemberhtgc:NetBaseSolutionsIncMember2022-09-300001280784htgc:PineappleEnergyLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMember2022-07-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:SioGeneTherapiesIncMember2022-09-300001280784htgc:JulyTwoThousandTwentyFourNotesMemberus-gaap:FairValueInputsLevel3Memberus-gaap:EstimateOfFairValueFairValueDisclosureMember2021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2022-09-300001280784htgc:ManufacturingTechnologyMemberhtgc:DebtInvestmentsUnderOneYearMaturityMember2021-12-310001280784htgc:HerculesAdviserLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberus-gaap:MemberUnitsMemberhtgc:MajorityOwnedControlInvestmentsMember2020-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:AcaciaPharmaIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-12-310001280784us-gaap:WarrantMemberus-gaap:MeasurementInputRevenueMultipleMembersrt:MinimumMemberhtgc:ValuationTechniqueLiquidationMemberus-gaap:FairValueInputsLevel3Member2022-09-300001280784htgc:EquityInvestmentsMemberhtgc:CommunicationsAndNetworkingMemberhtgc:PeerlessNetworkHoldingsIncMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784country:IE2021-12-310001280784htgc:EquityInvestmentsMemberhtgc:CommunicationsAndNetworkingMemberhtgc:PeerlessNetworkHoldingsIncMemberus-gaap:SeriesAPreferredStockMember2021-01-012021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:RVShareLimitedLiabilityCompanyMember2022-09-300001280784us-gaap:EquitySecuritiesMemberus-gaap:MeasurementInputRevenueMultipleMembersrt:MaximumMemberus-gaap:FairValueInputsLevel3Memberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:MeasurementInputsProbabilityWeightingOfAlternativeOutcomesMembersrt:MinimumMemberhtgc:ValuationTechniqueLiquidationMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:LowerMiddleMarketMember2022-09-300001280784htgc:UnusedFacilityOtherFeesMemberhtgc:WellsFacilityMember2021-01-012021-09-300001280784htgc:MeasurementInputPremiumDiscountMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberhtgc:LowerMiddleMarketMemberhtgc:MarketComparableCompaniesMember2021-12-310001280784us-gaap:PreferredStockMemberus-gaap:SalesRevenueNetMemberhtgc:InvestmentTypeConcentrationRiskMember2022-01-012022-09-300001280784htgc:SurgicalDevicesMemberhtgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMember2021-01-012021-12-310001280784htgc:XFourPharmaceuticalsIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2022-09-300001280784us-gaap:CarryingReportedAmountFairValueDisclosureMemberhtgc:FebruaryTwoThousandTwentyFiveNotesMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:AutomationAnyWhereIncMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:MadrigalPharmaceuticalIncMember2022-09-300001280784htgc:SignalMediaLimitedMemberhtgc:DebtInvestmentsMember2021-12-310001280784us-gaap:SeriesEPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:MedroboticsCorporationMemberhtgc:MedicalDevicesAndEquipmentMember2021-01-012021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:RhinoLabsIncorporationMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:DebtInvestmentMemberhtgc:SustainableAndRenewableTechnologyMember2022-09-300001280784htgc:SurgicalDevicesMemberhtgc:EquityInvestmentsMember2022-09-300001280784htgc:ReischlingPressIncMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:MadrigalPharmaceuticalIncMemberhtgc:ExitFeeMember2022-09-300001280784htgc:InvestmentMember2021-12-310001280784htgc:EquityInvestmentsMemberhtgc:SeriesThreePreferredStockMemberhtgc:SoftwareMemberhtgc:DruvaHoldingsIncMember2022-09-300001280784htgc:AppDirectIncorporationMemberhtgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SustainableAndRenewableTechnologyMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:CenturyTherapeuticsIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:MeasurementInputPremiumDiscountMembersrt:MinimumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:LowerMiddleMarketMemberhtgc:MarketComparableCompaniesMember2021-12-310001280784us-gaap:UnsecuredDebtMember2022-09-300001280784htgc:DebtInvestmentsMemberhtgc:BicycleTherapeuticsPLCMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:DermavantSciencesLtdMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:RVShareLimitedLiabilityCompanyMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:IvericBioGeneTherapyLlcMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:WarrantInvestmentMemberhtgc:FlowonixMedicalIncorporatedMemberhtgc:MedicalDevicesAndEquipmentMember2021-12-310001280784htgc:ExpectedRealizableValueMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:LowerMiddleMarketMember2021-12-310001280784htgc:CommonStockInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:AppreciationMember2022-01-012022-09-300001280784us-gaap:CarryingReportedAmountFairValueDisclosureMemberhtgc:JuneTwoThousandTwentyFiveThreeYearNotesMember2022-09-300001280784htgc:ImpossibleFoodsIncMemberhtgc:DebtInvestmentsUnderOneYearMaturityMemberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784htgc:DebtInvestmentsMemberhtgc:PhathomPharmaceuticalsIncMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:SeatGeekIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-3000012807842022-10-270001280784us-gaap:WarrantMemberhtgc:ElectronicsComputerHardwareMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberus-gaap:CommonStockMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2022-09-300001280784htgc:PineappleEnergyLLCMemberhtgc:SeniorDebtMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMember2022-01-012022-09-300001280784us-gaap:RestrictedStockMemberhtgc:CapitalInExcessOfParValueMember2022-01-012022-09-300001280784us-gaap:CarryingReportedAmountFairValueDisclosureMember2022-09-300001280784htgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:InformationServicesMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:GenoceaBiosciencesIncMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:JuneTwoThousandTwentyFiveNotesMember2021-01-012021-09-300001280784us-gaap:SeriesCPreferredStockMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberhtgc:NorthSeaTherapeuticsMember2021-01-012021-12-310001280784htgc:RoyaltyContractMemberhtgc:PhathomPharmaceuticalsIncMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:AffiliateInvestmentsMember2022-01-012022-09-300001280784htgc:SMBCFacilityMemberhtgc:UnusedFacilityOtherFeesMember2022-01-012022-09-300001280784us-gaap:EmployeeStockOptionMember2021-07-012021-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:CommunicationsAndNetworkingMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:RocketLabGlobalServicesLLCMemberhtgc:ExitFeeMember2022-09-300001280784htgc:BrainCorporationMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:AldeyraTherapeuticsIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784us-gaap:PreferredStockMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2022-01-012022-09-300001280784us-gaap:CashEquivalentsMemberhtgc:GSFinancialSquareGovernmentFundMember2022-09-300001280784htgc:DrugDeliveryMemberhtgc:EquityInvestmentsMemberhtgc:BioQPharmaIncorporatedMemberus-gaap:SeriesDPreferredStockMember2021-12-310001280784us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2020-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:RhinoLabsIncorporationMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:SurgicalDevicesMemberus-gaap:SeriesCPreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:GynesonicsIncMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMemberhtgc:CerosIncorporationMember2021-12-310001280784htgc:InvestmentFundsVehiclesMember2021-12-310001280784htgc:SeptemberTwoThousandTwentySixNotesMember2022-07-012022-09-300001280784htgc:SemiconductorsMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:FungibleIncorporationMember2021-01-012021-12-310001280784htgc:HerculesAdviserLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberus-gaap:UnsecuredDebtMemberhtgc:MajorityOwnedControlInvestmentsMember2022-01-012022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesDPreferredStockMemberhtgc:LendioIncMember2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsUnderOneYearMaturityMemberhtgc:RegentEducationMember2021-12-310001280784htgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMember2022-01-012022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:SkywordIncorporatinMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesBPreferredStockMember2022-01-012022-09-300001280784htgc:DebtInvestmentMember2021-01-012021-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:BrickellBiotechIncMember2021-01-012021-12-310001280784us-gaap:EquitySecuritiesMemberus-gaap:MeasurementInputRevenueMultipleMemberhtgc:ValuationTechniqueLiquidationMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMember2022-09-300001280784htgc:SBADebenturesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2022-09-300001280784htgc:AdviserSubsidiaryMember2022-09-300001280784country:IE2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:TGTherapeuticsIncMember2021-12-310001280784htgc:TwoThousandTwentyTwoConvertibleNotesMember2021-07-012021-09-300001280784htgc:MeasurementInputPremiumDiscountMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberhtgc:SustainableAndRenewableTechnologyMemberhtgc:MarketComparableCompaniesMember2022-09-300001280784us-gaap:GeographicConcentrationRiskMemberus-gaap:SalesRevenueNetMembercountry:DE2021-01-012021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:AxsomeTherapeuticsIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:CellarityIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:PollenIncMemberhtgc:SeniorsecuredtrancheaMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMember2021-12-310001280784htgc:July2024NotesMember2022-09-300001280784htgc:NuvoloTechnologiesCorporationMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:TotalInvestmentsBeforeCashAndCashEquivalentMember2022-09-300001280784us-gaap:RestrictedStockMemberhtgc:CapitalInExcessOfParValueMember2021-07-012021-09-300001280784us-gaap:SeriesEPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:YipitLLCMemberhtgc:InformationServicesMember2021-01-012021-12-310001280784htgc:SBADebenturesIssuedOnDecemberTwentyTwoThousandAndTwentyOneMember2022-01-012022-09-300001280784htgc:AytuBioScienceIncMemberhtgc:DrugDeliveryMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:ConsumerAndBusinessProductsMemberhtgc:TheNeatCompanyMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:BrigadeGroupIncMember2021-12-310001280784htgc:DebtInvestmentsUnderOneYearMaturityMemberhtgc:SustainableAndRenewableTechnologyMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:CellarityIncMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesBPreferredStockMember2022-01-012022-09-300001280784htgc:EquityInvestmentsMemberhtgc:CommonUnitsMemberhtgc:NantEnergyLLCMemberhtgc:SustainableAndRenewableTechnologyMember2021-01-012021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMember2021-12-310001280784us-gaap:WarrantMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesDPreferredStockMemberhtgc:LendioIncMember2021-01-012021-12-310001280784htgc:UnusedFacilityOtherFeesMemberhtgc:TwoThousandTwentySevenAssetBackedNotesMember2021-01-012021-09-300001280784htgc:WarrantInvestmentMemberhtgc:MediaContentInfoMember2021-12-310001280784htgc:ConvertibleNoteDiscountsAmortizationMember2022-01-012022-09-300001280784htgc:MUFGBankFacilityMember2022-09-300001280784htgc:ConsumerAndBusinessProductsMemberhtgc:EquityInvestmentsMember2021-12-310001280784htgc:DebtInvestmentsMember2022-09-300001280784htgc:SustainableAndRenewableTechnologyMember2022-09-300001280784us-gaap:SeriesEPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:SoftwareMemberhtgc:VeranaHealthIncMember2022-09-300001280784htgc:UnsecuredDebtFourteenPointFiveZeroPercentageMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:DiversifiedFinancialServicesMemberhtgc:MajorityOwnedControlInvestmentsMember2021-12-310001280784htgc:ZoomMediaGroupIncMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesAPreferredStockMemberhtgc:MediaContentInfoMember2022-01-012022-09-300001280784htgc:DepreciationMemberus-gaap:FairValueInputsLevel3Memberus-gaap:DebtMember2022-01-012022-09-300001280784htgc:EquityInvestmentsMemberhtgc:SeriesAThreePreferredStockMemberhtgc:CapLinkedIncMemberhtgc:SoftwareMember2021-12-310001280784htgc:WarrantInvestmentMemberhtgc:FlowonixMedicalIncorporatedMemberhtgc:PreferredSeriesBBMemberhtgc:MedicalDevicesAndEquipmentMember2021-01-012021-12-310001280784htgc:SeptemberTwoThousandTwentySixNotesMember2022-09-300001280784us-gaap:PreferredStockMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2021-12-310001280784country:NLus-gaap:GeographicConcentrationRiskMemberus-gaap:SalesRevenueNetMember2022-01-012022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMember2021-01-012021-09-300001280784htgc:TwoThousandThirtyThreeNotesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2022-09-300001280784htgc:TotalInvestmentsWithCashAndCashEquivalentMember2022-09-300001280784htgc:January2027NotesMember2022-01-200001280784htgc:SeniorSecuredDebtMemberhtgc:GroveCollaborativeIncMemberhtgc:ConsumerAndBusinessProductsMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:SBADebenturesIssuedOnNovemberThirtyTwoThousandAndTwentyOneMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:BicycleTherapeuticsPLCMember2022-09-300001280784htgc:EquityInvestmentsMemberhtgc:ViewRayIncMemberus-gaap:CommonStockMemberhtgc:MedicalDevicesAndEquipmentMember2022-09-300001280784htgc:EquityInvestmentsMemberhtgc:SeriesAThreePreferredStockMemberhtgc:CapLinkedIncMemberhtgc:SoftwareMember2021-01-012021-12-310001280784us-gaap:EquitySecuritiesMemberus-gaap:MeasurementInputRevenueMultipleMembersrt:MinimumMemberus-gaap:FairValueInputsLevel3Memberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:PollenIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:UnityBiotechnologyIncMember2021-12-310001280784htgc:PineappleEnergyLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberus-gaap:CommonStockMember2022-09-300001280784htgc:MeasurementInputsProbabilityWeightingOfAlternativeOutcomesMemberhtgc:TechnologyMembersrt:MaximumMemberhtgc:ValuationTechniqueLiquidationMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Member2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:TGTherapeuticsIncMember2022-09-300001280784htgc:HalioIncMemberhtgc:SustainableAndRenewableTechnologyMember2022-09-300001280784us-gaap:FairValueInputsLevel3Memberus-gaap:CommonStockMemberus-gaap:FairValueMeasurementsRecurringMember2021-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:BiomXINCMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2021-12-310001280784htgc:TechnologyMembersrt:MaximumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputHypotheticalMarketYieldMemberhtgc:MarketComparableCompaniesMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:DashlaneIncorporationMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:SemiconductorsMemberhtgc:EquityInvestmentsMember2021-12-310001280784htgc:EquityInvestmentsMemberhtgc:MedicalDevicesAndEquipmentMember2021-12-310001280784us-gaap:EquitySecuritiesMemberus-gaap:MeasurementInputRevenueMultipleMembersrt:MinimumMemberhtgc:ValuationTechniqueLiquidationMemberus-gaap:FairValueInputsLevel3Member2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:SnagajobcomIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784us-gaap:RestrictedStockMemberus-gaap:CommonStockMember2021-07-012021-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:BicycleTherapeuticsPLCMember2022-01-012022-09-300001280784htgc:AgrividaIncMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesDPreferredStockMemberhtgc:SustainableAndRenewableTechnologyMember2022-01-012022-09-300001280784htgc:PollenIncMemberhtgc:SeniorsecuredtrancheaMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:SurgicalDevicesMemberhtgc:EquityInvestmentsMemberus-gaap:SeriesBPreferredStockMemberhtgc:GynesonicsIncMember2021-01-012021-12-310001280784htgc:CommunicationsAndNetworkingMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:TGTherapeuticsIncMemberhtgc:ExitFeeMember2022-09-300001280784htgc:WarrantInvestmentMemberhtgc:HalioIncPKKinestralTechnologiesIncMemberus-gaap:SeriesBPreferredStockMemberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784htgc:JanuaryTwoThousandTwentySevenNotesMember2022-01-012022-09-300001280784htgc:DiversifiedFinancialServicesMember2021-12-310001280784htgc:TarsusPharmaceuticalsIncMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:SemiconductorsMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:XFourPharmaceuticalsIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:SemiconductorsMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:FungibleIncorporationMember2021-12-310001280784htgc:WarrantInvestmentMemberhtgc:SoftwareMemberhtgc:SeriesJuniorOnePreferredMemberhtgc:SignPostIncMember2022-01-012022-09-300001280784us-gaap:ConvertibleDebtSecuritiesMember2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:AldeyraTherapeuticsIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-3100012807842021-12-310001280784htgc:ConstructorIoCorporationMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberus-gaap:SeriesCPreferredStockMemberhtgc:NorthSeaTherapeuticsMemberhtgc:EquityInvestmentsMember2022-01-012022-09-300001280784htgc:TwoThousandTwentyTwoNotesMember2021-07-012021-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberus-gaap:CommonClassAMemberhtgc:SavageXHoldingLLCMember2021-12-310001280784us-gaap:ConvertibleDebtSecuritiesMember2022-07-012022-09-300001280784htgc:MyovantSciencesLtdMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:CapellaSpaceCorporationMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:InformationServicesMember2022-09-300001280784us-gaap:WarrantMemberus-gaap:ValuationTechniqueOptionPricingModelMemberus-gaap:FairValueInputsLevel3Member2022-09-300001280784htgc:TechnologyMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMemberus-gaap:MeasurementInputDiscountRateMembersrt:WeightedAverageMember2022-09-300001280784htgc:WorldremitGroupLimitedMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesDPreferredStockMember2022-09-300001280784htgc:PineappleEnergyLLCMemberhtgc:EquityInvestmentsMemberus-gaap:CommonClassAMemberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784htgc:WarrantInvestmentMemberhtgc:ManufacturingTechnologyMemberus-gaap:CommonStockMemberhtgc:XometryIncMember2022-01-012022-09-300001280784htgc:DebtInvestmentMemberhtgc:InformationServicesMember2022-09-300001280784us-gaap:SalesRevenueNetMemberhtgc:FirstLienAllAssetsMemberhtgc:CollateralTypeConcentrationRiskMember2021-01-012021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberus-gaap:CommonStockMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2020-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:CarwowLimitedMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-09-300001280784htgc:JulyTwoThousandTwentyFourNotesMemberhtgc:UnusedFacilityOtherFeesMember2021-01-012021-09-300001280784us-gaap:RestrictedStockUnitsRSUMember2022-01-012022-09-300001280784htgc:TechnologyMembersrt:MaximumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputHypotheticalMarketYieldMemberhtgc:MarketComparableCompaniesMember2022-09-300001280784us-gaap:EquitySecuritiesMembersrt:MaximumMemberus-gaap:ValuationTechniqueOptionPricingModelMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputMarketEquityAdjustmentMember2022-09-300001280784htgc:CommunicationsAndNetworkingMemberhtgc:SpringMobileSolutionsIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:MeasurementInputsProbabilityWeightingOfAlternativeOutcomesMembersrt:MinimumMemberhtgc:ExpectedRealizableValueMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:LowerMiddleMarketMember2021-12-310001280784htgc:CommunicationsAndNetworkingMemberhtgc:SpringMobileSolutionsIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:EquityInvestmentsMemberhtgc:GelesisIncMemberus-gaap:CommonStockMemberhtgc:MedicalDevicesAndEquipmentMember2021-01-012021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:SeniorDebtMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2022-01-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:AveoPharmaceuticalsIncMember2022-01-012022-09-300001280784htgc:DebtInvestmentsMemberhtgc:LogicworksMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:EloxxPharmaceuticalsIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2021-12-310001280784htgc:MUFGBankFacilityMemberhtgc:OneMonthSecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember2022-01-012022-09-300001280784htgc:SkydioIncorporationMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:DiversifiedFinancialServicesMemberus-gaap:UnsecuredDebtMember2021-12-310001280784htgc:SBADebenturesIssuedOnJulyTwentyEightTwoThousandAndTwentyOneMember2021-12-310001280784htgc:SurgicalDevicesMemberus-gaap:SeriesEPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:GynesonicsIncMember2021-01-012021-12-310001280784htgc:HealthcareServicesOtherMemberhtgc:DebtInvestmentsGreaterThanFiveYearsMaturityMember2022-09-300001280784htgc:HumanigenIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:DebtInvestmentsMemberhtgc:ManufacturingTechnologyMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:MacroFabIncorporationMemberhtgc:ManufacturingTechnologyMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:ProterraIncMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:SustainableAndRenewableTechnologyMember2021-01-012021-12-310001280784htgc:ZepzPKAWorldremitGroupLimitedMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesDPreferredStockMember2021-01-012021-12-310001280784htgc:DebtInvestmentsMemberhtgc:IkonScienceLimitedMember2022-09-300001280784htgc:BlackCrowAIIncMemberhtgc:PromissoryNotesMember2022-09-300001280784htgc:SingleStoreIncMemberhtgc:EquityInvestmentsMemberhtgc:SoftwareMember2022-09-300001280784htgc:CommonStockInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:AppreciationMember2021-01-012021-09-300001280784htgc:ControlInvestmentsMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMember2021-01-012021-09-300001280784htgc:JuneTwoThousandTwentyFiveNotesMemberus-gaap:CarryingReportedAmountFairValueDisclosureMember2021-12-310001280784htgc:SeniorDebtMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:SolarSpectrumHoldingsLLCMember2021-09-300001280784htgc:SustainableAndRenewableTechnologyMember2021-12-310001280784htgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMemberhtgc:SoftwareMember2022-01-012022-09-300001280784htgc:OakStreetHealthIncMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:ChemocentryxIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784us-gaap:WarrantMemberus-gaap:MeasurementInputEbitdaMultipleMembersrt:MaximumMemberus-gaap:FairValueInputsLevel3Memberhtgc:MarketComparableCompaniesMember2021-12-310001280784htgc:SeniorSecuredDebtMemberus-gaap:FairValueMeasurementsRecurringMember2021-12-310001280784us-gaap:ValuationTechniqueDiscountedCashFlowMemberus-gaap:EquitySecuritiesMembersrt:MinimumMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:SeresTherapeuticsIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784us-gaap:PreferredStockMemberus-gaap:FairValueMeasurementsRecurringMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ScynexisIncMember2021-12-310001280784htgc:DeferredFeesMember2021-12-310001280784htgc:FirstLienIpMemberus-gaap:SalesRevenueNetMemberhtgc:CollateralTypeConcentrationRiskMember2022-01-012022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:SnagajobcomIncMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesAPreferredStockMember2021-01-012021-12-310001280784htgc:EqualityHealthLLCMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:RhinoLabsIncorporationMemberhtgc:EquityInvestmentsMemberhtgc:SeriesBTwoPreferredStockMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:UdacityIncMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:AldeyraTherapeuticsIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:CellarityIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:SurgicalDevicesMemberhtgc:EquityInvestmentsMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:KaleidoBiosciencesIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:DebtIssuanceCostMember2022-02-222022-02-220001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:AvaloTherapeuticsIncMember2021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:OtherControlInvestmentsMember2021-01-012021-09-300001280784htgc:HerculesAdviserLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberus-gaap:UnsecuredDebtMemberhtgc:MajorityOwnedControlInvestmentsMember2021-09-300001280784htgc:EquityInvestmentsMemberhtgc:CommonUnitsMemberhtgc:CoronadoAestheticsLLCMemberhtgc:MedicalDevicesAndEquipmentMember2021-01-012021-12-310001280784htgc:SeptemberTwoThousandTwentySixNotesMemberhtgc:UnusedFacilityOtherFeesMember2021-07-012021-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:LogicworksMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:NerdyIncMember2021-12-310001280784htgc:MarchTwoThousandTwentySixBNotesMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:GibraltarBusinessCapitalLLCMember2022-01-012022-09-300001280784htgc:KhorosPKLithiumTechnologiesMemberhtgc:DebtInvestmentsMember2022-09-300001280784us-gaap-supplement:InvestmentUnaffiliatedIssuerMember2022-01-012022-09-300001280784htgc:WarrantInvestmentMemberhtgc:MediaContentInfoMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:MajorityOwnedControlInvestmentsMemberus-gaap:UnsecuredDebtMember2022-01-012022-09-300001280784htgc:MeasurementInputPremiumDiscountMemberhtgc:MedicalDevicesMembersrt:MinimumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DashlaneIncorporationMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMember2022-09-300001280784us-gaap:IncomeApproachValuationTechniqueMemberhtgc:MeasurementInputsProbabilityWeightingOfAlternativeOutcomesMemberhtgc:TechnologyMembersrt:MaximumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Member2022-09-300001280784us-gaap:GeographicConcentrationRiskMemberus-gaap:SalesRevenueNetMembercountry:US2021-01-012021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:OtherControlInvestmentsMember2021-09-300001280784us-gaap:SeriesFPreferredStockMemberhtgc:SingleStoreIncMemberhtgc:EquityInvestmentsMemberhtgc:SoftwareMember2021-01-012021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:BlackCrowAIIncMember2022-01-012022-09-300001280784htgc:MeasurementInputPremiumDiscountMemberhtgc:MedicalDevicesMembersrt:MaximumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:SeniorsecuredtrancheaMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:TGTherapeuticsIncMember2021-12-310001280784htgc:SemiconductorsMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:XometryIncMember2021-12-310001280784htgc:CommunicationsAndNetworkingMember2021-12-310001280784us-gaap:RestrictedStockUnitsRSUMember2022-07-012022-09-300001280784srt:MaximumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputHypotheticalMarketYieldMemberhtgc:SustainableAndRenewableTechnologyMemberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:DebtInvestmentsMemberhtgc:AtaiLifeSciencesNVMember2022-09-300001280784us-gaap:WarrantMembersrt:MinimumMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputMarketEquityAdjustmentMemberhtgc:ValuationTechniqueMarketAdjustedOpmBacksolveMember2021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMember2021-09-300001280784us-gaap:WarrantMemberus-gaap:MeasurementInputDiscountForLackOfMarketabilityMembersrt:MinimumMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MarketApproachValuationTechniqueMember2022-09-300001280784htgc:XFourPharmaceuticalsIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:MixpanelIncMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:SignalMediaLimitedMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:InformationServicesMemberhtgc:ExitFeeMember2022-09-300001280784htgc:PineappleEnergyLLCMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:PhathomPharmaceuticalsIncMember2021-12-310001280784us-gaap:RestrictedStockMember2022-01-012022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:CoronadoAestheticsLLCMemberus-gaap:CommonStockMemberhtgc:MajorityOwnedControlInvestmentsMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:ImpervaIncMemberhtgc:DebtInvestmentsGreaterThanFiveYearsMaturityMemberhtgc:SoftwareMember2021-12-310001280784us-gaap:FairValueInputsLevel3Memberhtgc:FebruaryTwoThousandTwentyFiveNotesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2021-12-310001280784htgc:HerculesAdviserLLCMemberhtgc:EquityInvestmentsMemberhtgc:DiversifiedFinancialServicesMemberus-gaap:MemberUnitsMember2022-01-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:ScynexisIncMember2022-01-012022-09-300001280784htgc:DebtInvestmentsUnderOneYearMaturityMemberhtgc:DiversifiedFinancialServicesMember2021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMember2021-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:LyftIncMemberus-gaap:CommonStockMember2022-09-300001280784htgc:IntuityMedicalIncMemberhtgc:WarrantInvestmentMemberhtgc:SeriesBOnePreferredStockMemberhtgc:MedicalDevicesAndEquipmentMember2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:CarwowLimitedMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberus-gaap:PreferredStockMemberhtgc:BlackCrowAIIncMember2022-01-012022-09-300001280784htgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:DiversifiedFinancialServicesMemberhtgc:GibraltarBusinessCapitalLLCMember2021-01-012021-12-310001280784htgc:DrugDeliveryMemberhtgc:EquityInvestmentsMemberhtgc:AcelRxPharmaceuticalsIncMemberus-gaap:CommonStockMember2022-09-300001280784htgc:TwoThousandTwentyTwoNotesMemberus-gaap:CarryingReportedAmountFairValueDisclosureMember2021-12-310001280784htgc:WarrantInvestmentMemberhtgc:VideoAmpIncMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2022-09-300001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:MedicalDevicesAndEquipmentMemberhtgc:TelaBioIncMember2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:SemiconductorsMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:FungibleIncorporationMemberhtgc:ExitFeeMember2022-09-300001280784htgc:FebruaryTwoThousandTwentyFiveNotesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2021-12-310001280784htgc:PineappleEnergyLLCMemberhtgc:SeniorsecuredtrancheaMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784htgc:YipitLLCMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:HalioIncMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesBPreferredStockMemberhtgc:SustainableAndRenewableTechnologyMember2022-01-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:HilleVaxIncMember2022-01-012022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:SeniorsecuredtranchebMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:TecturaCorporationMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMember2022-01-012022-09-300001280784us-gaap:SeriesEPreferredStockMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:RedshiftBioanalyticsIncMemberhtgc:WarrantInvestmentMember2022-01-012022-09-300001280784htgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMember2021-12-310001280784htgc:PharmaceuticalsMembersrt:MinimumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputHypotheticalMarketYieldMemberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:WorldremitGroupLimitedMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784us-gaap:EquitySecuritiesMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MarketApproachValuationTechniqueMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:GroveCollaborativeIncMemberhtgc:ConsumerAndBusinessProductsMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:EquityInvestmentsMemberhtgc:HealthcareServicesOtherMember2021-12-310001280784htgc:SBADebenturesIssuedOnDecemberTwentyThreeTwoThousandAndTwentyOneMember2021-12-310001280784us-gaap:SubsequentEventMemberhtgc:BaseAndSupplementalDividendMember2022-10-132022-10-130001280784htgc:SurgicalDevicesMember2021-12-310001280784htgc:PineappleEnergyLLCMemberhtgc:SeniorDebtMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMember2022-09-300001280784htgc:MeasurementInputsProbabilityWeightingOfAlternativeOutcomesMemberhtgc:ExpectedRealizableValueMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberhtgc:LowerMiddleMarketMember2021-12-310001280784us-gaap:EquitySecuritiesMemberhtgc:ValuationTechniqueLiquidationMemberus-gaap:FairValueInputsLevel3Member2022-09-300001280784us-gaap:FairValueInputsLevel3Memberhtgc:WarrantInvestmentMemberhtgc:AppreciationMember2021-01-012021-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:SnagajobcomIncMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesAPreferredStockMember2022-09-300001280784htgc:EquityInvestmentsMemberhtgc:DiversifiedFinancialServicesMember2022-09-300001280784htgc:SBADebenturesIssuedOnNovemberFifteenTwoThousandAndTwentyOneMember2022-01-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:GenoceaBiosciencesIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784us-gaap:EquitySecuritiesMemberhtgc:ValuationTechniqueOtherMemberus-gaap:FairValueInputsLevel3Member2022-09-300001280784htgc:SBADebenturesIssuedOnNovemberOneTwoThousandAndTwentyOneMember2022-01-012022-09-300001280784us-gaap:EquitySecuritiesMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MarketApproachValuationTechniqueMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:EnmarkSystemsIncorporationMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMember2021-12-310001280784htgc:TwoThousandTwentyTwoConvertibleNotesMemberhtgc:UnusedFacilityOtherFeesMember2021-07-012021-09-300001280784htgc:DepreciationMemberus-gaap:FairValueInputsLevel3Memberhtgc:PreferredStockInvestmentMember2022-01-012022-09-300001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:LocusRoboticsCorporationMemberhtgc:ElectronicsComputerHardwareMember2022-09-300001280784htgc:ExpectedRealizableValueMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784htgc:AmpionPBCMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SustainableAndRenewableTechnologyMember2022-01-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:GenoceaBiosciencesIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:AlbireoPharmaIncMember2021-12-310001280784us-gaap:PreferredStockMember2021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:SeniorDebtMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2021-09-300001280784htgc:HerculesAdviserLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:MajorityOwnedControlInvestmentsMember2021-12-310001280784htgc:DebtInvestmentsMember2021-12-310001280784htgc:DronedeployIncorporationMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:March2026ANotesMember2020-11-040001280784htgc:SeriesATwoPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:CoronadoAestheticsLLCMemberhtgc:MedicalDevicesAndEquipmentMember2022-09-300001280784htgc:MeasurementInputPremiumDiscountMembersrt:MaximumMemberhtgc:PharmaceuticalsMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:UberTechnologiesIncMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:AlladaptImmunotherapeuticsincMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:SeriesAAPreferredStockMemberhtgc:TheFactionGroupLLCMemberhtgc:WarrantInvestmentMember2022-09-300001280784htgc:TwoThousandTwentyTwoConvertibleNotesMember2021-12-310001280784htgc:HealthcareServicesOtherMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:SurgicalDevicesMemberhtgc:EquityInvestmentsMemberhtgc:GynesonicsIncMember2021-12-310001280784htgc:JuneTwoThousandTwentyFiveNotesMemberus-gaap:FairValueInputsLevel3Memberus-gaap:EstimateOfFairValueFairValueDisclosureMember2021-12-310001280784htgc:InvestmentFundsAndVehiclesMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:CloudBoltSoftwareIncorporationMemberhtgc:ExitFeeMember2022-09-300001280784htgc:UnusedFacilityOtherFeesMemberhtgc:SBADebenturesMember2021-01-012021-09-300001280784htgc:MedicalDevicesMembersrt:MaximumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMemberus-gaap:MeasurementInputDiscountRateMember2022-09-300001280784htgc:ConsumerAndBusinessProductsMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:EloxxPharmaceuticalsIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:SkydioIncorporationMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:ElectronicsComputerHardwareMember2022-09-300001280784htgc:WarrantInvestmentMemberhtgc:FlowonixMedicalIncorporatedMemberhtgc:PreferredSeriesBBMemberhtgc:MedicalDevicesAndEquipmentMember2022-01-012022-09-300001280784us-gaap:IncomeApproachValuationTechniqueMemberhtgc:MeasurementInputsProbabilityWeightingOfAlternativeOutcomesMemberhtgc:TechnologyMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMember2022-09-300001280784us-gaap:MoneyMarketFundsMemberus-gaap:FairValueMeasurementsRecurringMember2022-09-300001280784htgc:SurgicalDevicesMemberus-gaap:SeriesEPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:GynesonicsIncMember2022-09-300001280784htgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:ZetaGlobalCorpMemberhtgc:InformationServicesMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:AgilenceIncorporationMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:PymetricsIncorporationMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2021-01-012021-12-310001280784htgc:BlackCrowAIIncMember2021-12-310001280784us-gaap:RestrictedStockMember2021-01-012021-09-300001280784htgc:AnnexCloudMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:TechnologyMembersrt:MinimumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputHypotheticalMarketYieldMemberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:DebtInvestmentsMember2021-12-310001280784htgc:ValoHealthLLCMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:SeriesBPreferredStockMember2022-09-300001280784htgc:AdviserFundsMember2022-01-012022-09-300001280784us-gaap:WarrantMemberhtgc:ValuationTechniqueLiquidationMemberus-gaap:FairValueInputsLevel3Member2022-09-300001280784htgc:MeasurementInputPremiumDiscountMembersrt:MinimumMemberhtgc:PharmaceuticalsMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MarketComparableCompaniesMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:NabrivaTherapeuticsMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:MUFGBankFacilityMember2022-07-012022-09-300001280784htgc:DebtInvestmentMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:SignalMediaLimitedMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:InformationServicesMember2022-09-300001280784htgc:SingleStoreIncMemberhtgc:WarrantInvestmentMemberhtgc:SoftwareMemberus-gaap:SeriesDPreferredStockMember2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:OakStreetHealthIncMemberhtgc:HealthcareServicesOtherMemberhtgc:DebtInvestmentsGreaterThanFiveYearsMaturityMember2022-09-300001280784htgc:EquityInvestmentsMemberhtgc:ViewRayIncMemberus-gaap:CommonStockMemberhtgc:MedicalDevicesAndEquipmentMember2021-12-310001280784htgc:DebtInvestmentsMemberhtgc:HilleVaxIncMember2022-09-300001280784htgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:DiversifiedFinancialServicesMember2022-09-300001280784htgc:JulyTwoThousandTwentyFourNotesMember2022-01-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberhtgc:AppliedMolecularTransportMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:ParatekPharmaceuticalsIncMember2021-01-012021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:ConsumerAndBusinessProductsMemberhtgc:TheNeatCompanyMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:HerculesAdviserLLCMemberhtgc:EquityInvestmentsMemberhtgc:DiversifiedFinancialServicesMemberus-gaap:MemberUnitsMember2021-01-012021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:NuvoloTechnologiesCorporationMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:SBADebenturesIssuedOnOctoberTwentyOneTwoThousandAndTwentyOneMember2021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2021-12-310001280784htgc:SurgicalDevicesMemberus-gaap:SeriesCPreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:GynesonicsIncMember2022-09-300001280784htgc:JulyTwoThousandTwentyFourNotesMemberhtgc:UnusedFacilityOtherFeesMember2021-07-012021-09-300001280784htgc:InformationServicesMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:HumanigenIncMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:GeronCorporationMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:ElectronicsComputerHardwareMember2022-09-300001280784htgc:ConsumerAndBusinessProductsMemberhtgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMember2021-01-012021-12-310001280784htgc:MyovantSciencesLtdMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:MarchTwoThousandTwentySixANotesMember2021-12-310001280784htgc:SemiconductorsMemberhtgc:WarrantInvestmentMember2021-12-310001280784htgc:WarrantInvestmentMemberhtgc:CapellaSpaceCorporationMemberus-gaap:CommonStockMemberhtgc:InformationServicesMember2021-01-012021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:UnsecuredDebtElevenPointFiveZeroPercentageMemberhtgc:DiversifiedFinancialServicesMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:MajorityOwnedControlInvestmentsMember2021-12-310001280784htgc:BrainCorporationMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2021-01-012021-12-310001280784htgc:TwoThousandTwentyTwoConvertibleNotesMember2017-01-250001280784htgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberhtgc:DareBiosciencesIncMemberus-gaap:CommonStockMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:AveoPharmaceuticalsIncMember2021-01-012021-12-310001280784us-gaap:WarrantMemberus-gaap:MeasurementInputRevenueMultipleMembersrt:MinimumMemberus-gaap:FairValueInputsLevel3Memberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:ConsumerAndBusinessProductsMemberhtgc:WarrantInvestmentMember2022-09-300001280784htgc:DronedeployIncorporationMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:UdacityIncMember2021-12-310001280784us-gaap:EquitySecuritiesMembersrt:MaximumMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputTangibleBookValueMultipleMemberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:PolyeraCorporationMemberus-gaap:SeriesCPreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:SustainableAndRenewableTechnologyMember2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:MacroFabIncorporationMemberhtgc:ManufacturingTechnologyMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:SBADebenturesMember2022-01-012022-09-300001280784us-gaap:FairValueInputsLevel3Memberus-gaap:UnsecuredDebtMemberus-gaap:FairValueMeasurementsRecurringMember2022-09-300001280784htgc:SurgicalDevicesMemberus-gaap:SeriesCPreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:GynesonicsIncMember2021-01-012021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberhtgc:HouzzIncorporationMemberus-gaap:CommonStockMember2021-12-310001280784htgc:PharmaceuticalsMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMemberus-gaap:MeasurementInputDiscountRateMembersrt:WeightedAverageMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:VeemIncorporationMemberhtgc:SeniorsecuredtrancheaMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:CommunicationsAndNetworkingMemberhtgc:WarrantInvestmentMember2022-09-300001280784htgc:DiscountsAmortizationMember2022-01-012022-09-300001280784htgc:MacroFabIncorporationMemberhtgc:ManufacturingTechnologyMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:XFourPharmaceuticalsIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2021-12-310001280784us-gaap:SalesRevenueNetMemberhtgc:FirstLienLastOutSeniorSecuredMemberhtgc:CollateralTypeConcentrationRiskMember2021-01-012021-12-310001280784htgc:GeographicLocationMember2022-01-012022-09-300001280784htgc:ServiceVestingAwardsMember2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DemandbaseIncorporationMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:NerdyIncMember2021-01-012021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:AxsomeTherapeuticsIncMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2022-09-300001280784htgc:OakStreetHealthIncMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:PolyeraCorporationMemberus-gaap:SeriesCPreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:MobileSolutionsServicesMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMember2022-09-300001280784htgc:HerculesAdviserLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMember2022-07-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:EnGeneIncMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:VeemIncorporationMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:DebtInvestmentsMemberhtgc:InformationServicesMember2021-12-310001280784us-gaap:FairValueMeasurementsRecurringMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:AlbireoPharmaIncMember2022-01-012022-09-300001280784us-gaap:GeographicConcentrationRiskMemberus-gaap:SalesRevenueNetMembercountry:IL2022-01-012022-09-300001280784htgc:ExcludingCashAndCashEquivalentMemberus-gaap:FairValueMeasurementsRecurringMember2022-09-300001280784htgc:UnusedFacilityOtherFeesMemberhtgc:TwoThousandThirtyThreeNotesMember2021-01-012021-09-300001280784htgc:EigenTechnologiesLimitedMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2022-09-300001280784us-gaap:VariableInterestEntityPrimaryBeneficiaryMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:NextrollIncorporationMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:OutsetMedicalIncMemberhtgc:MedicalDevicesAndEquipmentMember2021-12-310001280784htgc:EvernoteCorporationMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2021-12-310001280784htgc:PineappleEnergyLLCMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:ManufacturingTechnologyMemberhtgc:DebtInvestmentMember2021-12-310001280784htgc:MeasurementInputPremiumDiscountMemberhtgc:MedicalDevicesMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMembersrt:WeightedAverageMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:SeniorsecuredtrancheaMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:PhathomPharmaceuticalsIncMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:TFGHoldingIncMember2022-01-012022-09-300001280784htgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:TecturaCorporationMember2022-01-012022-09-300001280784htgc:SurgicalDevicesMemberus-gaap:SeriesFPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:GynesonicsIncMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:BiomXINCMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:DrugDeliveryMemberhtgc:EquityInvestmentsMemberhtgc:BioQPharmaIncorporatedMemberus-gaap:SeriesDPreferredStockMember2022-09-300001280784htgc:InvestmentFundsAndVehiclesMemberhtgc:SoftwareMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMemberhtgc:MixpanelIncMemberhtgc:ExitFeeMember2022-09-300001280784htgc:ConsumerAndBusinessProductsMemberhtgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMember2022-01-012022-09-300001280784htgc:DebtInvestmentsMemberhtgc:HilleVaxIncMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:RocketPharmaceuticalsLtdMember2022-01-012022-09-300001280784htgc:MarchTwoThousandTwentySixANotesMember2022-07-012022-09-300001280784us-gaap:SeniorLienMemberus-gaap:SalesRevenueNetMemberhtgc:CollateralTypeConcentrationRiskMember2021-01-012021-12-310001280784htgc:TwoThousandEighteenPlanAndDirectorPlanMember2018-06-280001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:RhinoLabsIncorporationMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-09-300001280784htgc:EquityInvestmentsMemberhtgc:SeriesAThreePreferredStockMemberhtgc:CapLinkedIncMemberhtgc:SoftwareMember2022-01-012022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:NextdoorComIncMemberus-gaap:CommonStockMember2021-12-310001280784htgc:ConsumerAndBusinessProductsMemberhtgc:TechStyleIncPKJustFabulousIncMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesBPreferredStockMember2021-01-012021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:IvericBioGeneTherapyLlcMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:CapRateMember2022-09-300001280784htgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMember2021-01-012021-12-310001280784us-gaap-supplement:InvestmentUnaffiliatedIssuerMember2021-12-310001280784htgc:SeriesATwoPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:CoronadoAestheticsLLCMemberhtgc:MedicalDevicesAndEquipmentMember2021-12-310001280784htgc:ElationHealthIncMemberhtgc:DebtInvestmentsMember2022-09-300001280784us-gaap:MeasurementInputEbitdaMultipleMemberus-gaap:EquitySecuritiesMembersrt:MaximumMemberus-gaap:FairValueInputsLevel3Memberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:LightbendIncMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberus-gaap:CommonClassAMemberhtgc:SavageXHoldingLLCMember2022-09-300001280784htgc:PolyeraCorporationMemberus-gaap:SeriesCPreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:SustainableAndRenewableTechnologyMember2021-01-012021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberhtgc:DareBiosciencesIncMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:WarrantInvestmentMemberhtgc:ElectronicsComputerHardwareMember2021-12-310001280784htgc:SurgicalDevicesMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:TransMedicsGroupIncPKTransmedicsIncMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:YumanityTherapeuticsIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberhtgc:SeriesGThreePreferredStockMemberhtgc:InteractionsCorporationMember2021-01-012021-12-310001280784htgc:ExitFeesAmortizationMember2022-01-012022-09-300001280784us-gaap:RestrictedStockUnitsRSUMember2021-01-012021-09-300001280784us-gaap:WarrantMemberus-gaap:MeasurementInputDiscountForLackOfMarketabilityMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberhtgc:MarketComparableCompaniesMember2022-09-300001280784us-gaap:MeasurementInputDiscountForLackOfMarketabilityMemberus-gaap:EquitySecuritiesMembersrt:MinimumMemberhtgc:ValuationTechniqueLiquidationMemberus-gaap:FairValueInputsLevel3Member2022-09-300001280784htgc:MedicalDevicesMembersrt:MinimumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMemberus-gaap:MeasurementInputDiscountRateMember2022-09-300001280784htgc:LightbendIncMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2022-01-012022-09-300001280784us-gaap:WarrantMemberus-gaap:MeasurementInputEbitdaMultipleMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberhtgc:MarketComparableCompaniesMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:SnagajobcomIncMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesBPreferredStockMember2021-12-310001280784us-gaap:ValuationTechniqueDiscountedCashFlowMemberus-gaap:EquitySecuritiesMembersrt:MaximumMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMember2021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:GibraltarBusinessCapitalLLCMember2021-07-012021-09-300001280784htgc:SkydioIncorporationMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:ElectronicsComputerHardwareMember2021-12-310001280784htgc:EqualityHealthLLCMemberhtgc:DebtInvestmentsMember2022-09-300001280784us-gaap:EstimateOfFairValueFairValueDisclosureMemberhtgc:SeptemberTwoThousandTwentySixNotesMember2021-12-310001280784htgc:DebtInvestmentsMemberhtgc:FulfilSolutionsIncMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:ElationHealthIncMemberhtgc:HealthcareServicesOtherMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:MeasurementInputsProbabilityWeightingOfAlternativeOutcomesMemberhtgc:TechnologyMembersrt:MaximumMemberhtgc:ValuationTechniqueLiquidationMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Member2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:DoorDashIncMemberus-gaap:CommonStockMember2022-09-300001280784us-gaap:RestrictedStockMember2021-01-012021-09-300001280784htgc:AssetBackedNotesMemberus-gaap:VariableInterestEntityPrimaryBeneficiaryMember2022-09-300001280784htgc:MUFGBankFacilityMemberhtgc:UnusedFacilityOtherFeesMember2022-07-012022-09-300001280784htgc:MeasurementInputPremiumDiscountMemberhtgc:PharmaceuticalsMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberhtgc:TricidaIncMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784us-gaap:CommonStockMember2022-09-300001280784us-gaap:RestrictedStockMember2022-01-012022-09-300001280784us-gaap:MeasurementInputEbitdaMultipleMemberus-gaap:EquitySecuritiesMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:UnusedFacilityOtherFeesMemberhtgc:WellsFacilityMember2021-07-012021-09-300001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMemberhtgc:CouchbaseIncMember2021-01-012021-12-310001280784htgc:EquityInvestmentsMemberhtgc:SprinklrIncMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2021-01-012021-12-310001280784htgc:UnusedFacilityOtherFeesMemberhtgc:MarchTwoThousandTwentySixANotesMember2022-07-012022-09-300001280784htgc:SeniorSecuredDebtMemberus-gaap:InterestRateFloorMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMemberhtgc:IkonScienceLimitedMember2021-12-310001280784htgc:ValuationTechniqueLiquidationMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:LowerMiddleMarketMember2021-12-310001280784us-gaap:WarrantMemberhtgc:CommunicationsAndNetworkingMember2022-09-300001280784us-gaap:EstimateOfFairValueFairValueDisclosureMemberhtgc:SeptemberTwoThousandTwentySixNotesMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:DynavaxTechnologiesMember2022-09-300001280784htgc:MeasurementInputPremiumDiscountMemberhtgc:ExpectedRealizableValueMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberhtgc:LowerMiddleMarketMember2021-12-310001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:DemandbaseIncorporationMemberhtgc:SoftwareMember2021-01-012021-12-310001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMemberhtgc:CouchbaseIncMember2022-01-012022-09-300001280784htgc:ValoHealthLLCMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:SeriesBPreferredStockMember2021-01-012021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:SavaraIncMember2022-01-012022-09-300001280784htgc:ValoHealthLLCMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-09-3000012807842021-06-300001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMemberhtgc:UdacityIncMember2021-01-012021-12-310001280784us-gaap:MeasurementInputEbitdaMultipleMemberus-gaap:EquitySecuritiesMembersrt:MinimumMemberus-gaap:FairValueInputsLevel3Memberhtgc:MarketComparableCompaniesMember2021-12-3100012807842022-02-220001280784us-gaap:WarrantMemberus-gaap:MeasurementInputDiscountForLackOfMarketabilityMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberhtgc:MarketComparableCompaniesMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:CybermaxxIntermediateHoldingsIncorporationMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SoftwareMember2022-09-300001280784htgc:DrugDeliveryMemberhtgc:EquityInvestmentsMemberhtgc:BioQPharmaIncorporatedMemberus-gaap:SeriesDPreferredStockMember2022-01-012022-09-300001280784srt:MinimumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMemberus-gaap:MeasurementInputDiscountRateMemberhtgc:LowerMiddleMarketMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerMemberhtgc:ControlAndAffiliateInvestmentsMember2021-01-012021-09-300001280784htgc:TechnologyMembersrt:MinimumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputHypotheticalMarketYieldMemberhtgc:MarketComparableCompaniesMember2021-12-310001280784us-gaap:FairValueInputsLevel2Memberhtgc:TwoThousandTwentyTwoNotesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2021-12-310001280784htgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:SprinklrIncMemberhtgc:SoftwareMember2022-09-300001280784htgc:PollenIncMemberhtgc:SeniorsecuredtranchebMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:SeriesATwoPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:CoronadoAestheticsLLCMemberhtgc:MedicalDevicesAndEquipmentMember2022-01-012022-09-300001280784htgc:GelesisIncMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:MedicalDevicesAndEquipmentMember2021-12-310001280784htgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:DebtMaturingWithinOneYearMember2022-09-300001280784htgc:EquityInvestmentsMemberhtgc:DiversifiedFinancialServicesMemberhtgc:GibraltarBusinessCapitalLLCMember2021-12-310001280784htgc:JuneTwoThousandTwentyFiveNotesMember2022-07-012022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMember2022-09-300001280784us-gaap:MeasurementInputEbitdaMultipleMemberus-gaap:EquitySecuritiesMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberhtgc:MarketComparableCompaniesMember2021-12-310001280784htgc:MarchTwoThousandTwentySixBNotesMember2022-07-012022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberus-gaap:CommonClassAMemberhtgc:SavageXHoldingLLCMember2022-01-012022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:VeemIncorporationMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2021-09-300001280784us-gaap:FairValueInputsLevel3Memberus-gaap:UnsecuredDebtMemberus-gaap:FairValueMeasurementsRecurringMember2021-01-012021-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberus-gaap:CommonStockMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2021-12-310001280784htgc:DistributableEarningsLossMember2021-01-012021-09-300001280784htgc:PerformanceAwardsMember2022-01-012022-09-300001280784htgc:EPayPolicyHoldingsLLCMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:SeriesAAPreferredStockMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:TheFactionGroupLLCMemberhtgc:WarrantInvestmentMember2021-12-310001280784htgc:AdviserSubsidiaryMember2022-07-012022-09-300001280784htgc:ConsumerAndBusinessProductsMemberhtgc:EquityInvestmentsMemberhtgc:TechStyleIncMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784us-gaap:CarryingReportedAmountFairValueDisclosureMemberhtgc:MarchTwoThousandTwentySixANotesMember2022-09-300001280784us-gaap:GeographicConcentrationRiskMemberus-gaap:SalesRevenueNetMembercountry:DE2022-01-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:AppliedGeneticTechnologiesCorporationMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784us-gaap:SeriesFPreferredStockMemberhtgc:SingleStoreIncMemberhtgc:EquityInvestmentsMemberhtgc:SoftwareMember2022-01-012022-09-300001280784htgc:TactAiTechnologiesIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2021-01-012021-12-310001280784htgc:WarrantInvestmentMemberhtgc:InformationServicesMember2022-09-300001280784htgc:September2026NotesMember2022-09-300001280784htgc:BrainCorporationMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:SemiconductorsMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:FungibleIncorporationMember2022-09-300001280784htgc:ConvertibleNoteDiscountsAmortizationMember2021-01-012021-09-300001280784htgc:TwoThousandTwentyTwoConvertibleNotesMember2022-01-012022-09-300001280784htgc:WarrantInvestmentMemberhtgc:FlowonixMedicalIncorporatedMemberhtgc:PreferredSeriesBBMemberhtgc:MedicalDevicesAndEquipmentMember2022-09-300001280784htgc:AlamarBiosciencesIncorporationMemberhtgc:DebtInvestmentsMember2022-09-300001280784us-gaap:SeriesFPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:MedroboticsCorporationMemberhtgc:MedicalDevicesAndEquipmentMember2021-01-012021-12-310001280784htgc:UnusedFacilityOtherFeesMemberhtgc:TwoThousandThirtyOneAssetBackedNotesMember2022-07-012022-09-300001280784htgc:FuzeIncMemberus-gaap:SeriesFPreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:SoftwareMember2021-12-310001280784htgc:CloudianIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2021-01-012021-12-310001280784htgc:UnusedFacilityOtherFeesMemberhtgc:SBADebenturesMember2022-07-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberhtgc:AvaloTherapeuticsIncMemberus-gaap:CommonStockMember2022-09-300001280784htgc:AlchemerLLCMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:ParatekPharmaceuticalsIncMember2022-01-012022-09-300001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMemberhtgc:EsmeLearningSolutionsIncorporationMember2022-09-300001280784htgc:BitsightTechnologiesIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2021-12-310001280784htgc:GeronCorporationMemberhtgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:NineZeroEightDevicesIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:ElectronicsComputerHardwareMember2022-09-300001280784htgc:DebtInvestmentsMemberhtgc:AtaiLifeSciencesNVMember2021-12-310001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberus-gaap:CommonStockMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:MajorityOwnedControlInvestmentsMember2020-12-310001280784htgc:UnusedFacilityOtherFeesMemberhtgc:JanuaryTwoThousandTwentySevenNotesMember2022-07-012022-09-300001280784us-gaap:SalesRevenueNetMemberhtgc:InvestmentTypeConcentrationRiskMember2022-01-012022-09-300001280784htgc:JulyTwoThousandTwentyFourNotesMemberus-gaap:CarryingReportedAmountFairValueDisclosureMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:FinchTherapeuticsGroupIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:SeriesOnePreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:InformationServicesMemberhtgc:NetBaseSolutionsIncMember2021-12-310001280784htgc:UnusedFacilityOtherFeesMemberhtgc:MarchTwoThousandTwentySixBNotesMember2021-07-012021-09-300001280784htgc:DebtInvestmentMemberhtgc:DiversifiedFinancialServicesMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:SyndaxPharmaceuticsIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMemberhtgc:LowerMiddleMarketMember2022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:InvestmentFundsVehiclesMemberhtgc:ForbionGrowthOpportunitiesFundICVMember2022-01-012022-09-300001280784htgc:SBADebenturesIssuedOnOctoberTwentyOneTwoThousandAndTwentyOneMember2022-01-012022-09-300001280784htgc:DebtInvestmentsUnderOneYearMaturityMemberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:FreshTracksTherapeuticsIncMember2022-09-300001280784htgc:JulyTwoThousandTwentyFourNotesMember2022-09-300001280784htgc:UnusedFacilityOtherFeesMemberhtgc:TwoThousandTwentyTwoNotesMember2021-07-012021-09-300001280784us-gaap:FairValueInputsLevel3Memberus-gaap:EstimateOfFairValueFairValueDisclosureMember2022-09-300001280784htgc:ConsumerAndBusinessProductsMemberhtgc:TheNeatCompanyMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-12-310001280784htgc:WorldremitGroupLimitedMemberhtgc:InternetConsumerAndBusinessServicesMemberus-gaap:SeriesEPreferredStockMemberhtgc:WarrantInvestmentMember2022-09-300001280784htgc:JulyTwoThousandTwentyFourNotesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:SeniorsecuredtranchebMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2021-12-310001280784htgc:DebtInvestmentsMemberhtgc:MedicalDevicesAndEquipmentMember2022-09-300001280784us-gaap:SeriesEPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:SoftwareMemberhtgc:VeranaHealthIncMember2021-01-012021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:FulfilSolutionsIncMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:EqualityHealthLLCMemberhtgc:HealthcareServicesOtherMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberus-gaap:SeriesCPreferredStockMemberhtgc:EquityInvestmentsMemberhtgc:ContentfulGlobalIncMember2021-12-310001280784htgc:JulyTwoThousandTwentyFourNotesMemberus-gaap:FairValueInputsLevel3Memberus-gaap:EstimateOfFairValueFairValueDisclosureMember2022-09-300001280784us-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsRecurringMember2021-12-310001280784htgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputHypotheticalMarketYieldMembersrt:WeightedAverageMemberhtgc:SustainableAndRenewableTechnologyMemberhtgc:MarketComparableCompaniesMember2022-09-300001280784us-gaap:PreferredStockMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:GibraltarBusinessCapitalLLCMemberhtgc:MajorityOwnedControlInvestmentsMember2020-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMemberhtgc:SavaraIncMember2022-09-300001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMemberhtgc:CutoverIncMember2022-01-012022-09-300001280784htgc:WarrantInvestmentMemberus-gaap:SeriesDPreferredStockMemberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:RedshiftBioanalyticsIncMemberhtgc:WarrantInvestmentMember2022-09-300001280784htgc:EquityAndWarrantInvestmentsMember2022-01-012022-09-300001280784htgc:CapitalInExcessOfParValueMember2022-01-012022-09-300001280784us-gaap:PreferredStockMemberhtgc:CoronadoAestheticsLLCMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:MajorityOwnedControlInvestmentsMember2022-01-012022-09-300001280784us-gaap:SubsequentEventMemberhtgc:SupplementalDividendMember2022-11-102022-11-100001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:DoorDashIncMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:UnfundedDebtCommitmentsMember2022-01-012022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:DebtInvestmentMember2021-12-310001280784htgc:SyndaxPharmaceuticsIncMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:CodiakBiosciencesIncMemberhtgc:ExitFeeMember2022-09-300001280784us-gaap:SalesRevenueNetMemberhtgc:InvestmentTypeConcentrationRiskMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberhtgc:HouzzIncorporationMemberus-gaap:CommonStockMember2022-09-300001280784htgc:IncludingCashAndCashEquivalentsMemberus-gaap:FairValueMeasurementsRecurringMember2021-12-310001280784htgc:TechnologyMemberhtgc:ValuationTechniqueLiquidationMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Member2021-12-310001280784htgc:SoftwareMemberhtgc:DebtInvestmentsUnderOneYearMaturityMember2021-12-310001280784us-gaap:PreferredStockMemberus-gaap-supplement:InvestmentAffiliatedIssuerNoncontrolledMemberhtgc:BlackCrowAIIncMember2021-12-310001280784us-gaap:SubsequentEventMemberhtgc:SupplementalDividendMember2022-10-132022-10-130001280784htgc:SBADebenturesIssuedOnJanuaryTwentyOneTwoThousandAndTwentyTwoMember2021-12-310001280784us-gaap:PreferredStockMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:YipitLLCMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:InformationServicesMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:EquityInvestmentsMemberhtgc:NextdoorComIncMemberus-gaap:CommonStockMember2022-09-300001280784htgc:SyndaxPharmaceuticsIncMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:EnGeneIncMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:GroveCollaborativeIncMemberhtgc:ConsumerAndBusinessProductsMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:InvestmentFundsAndVehiclesMemberhtgc:DrugDiscoveryAndDevelopmentMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:AmpionPBCMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SustainableAndRenewableTechnologyMemberhtgc:ExitFeeMember2022-09-3000012807842021-01-012021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:MotifBioPLCMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-12-310001280784htgc:SBADebenturesIssuedOnJuneTwentyFiveTwoThousandAndTwentyOneMember2022-09-300001280784htgc:WorldremitGroupLimitedMemberhtgc:InternetConsumerAndBusinessServicesMemberus-gaap:SeriesEPreferredStockMemberhtgc:WarrantInvestmentMember2022-01-012022-09-300001280784htgc:July2024NotesMember2022-01-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:AlbireoPharmaIncMember2022-09-300001280784htgc:MarchTwoThousandTwentySixANotesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2021-12-310001280784htgc:DashlaneIncorporationMemberhtgc:DebtInvestmentsMember2021-12-310001280784htgc:TwoThousandTwentyTwoNotesMember2022-07-012022-09-300001280784htgc:FinchTherapeuticsGroupIncMemberhtgc:DebtInvestmentsMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:NextrollIncorporationMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:SkywordIncorporatinMemberhtgc:WarrantInvestmentMemberus-gaap:SeriesBPreferredStockMember2021-01-012021-12-310001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:InformationServicesMemberhtgc:INMOBIIncMember2022-01-012022-09-300001280784htgc:EquityInvestmentsMemberhtgc:ZeroFoxIncMemberus-gaap:CommonStockMemberhtgc:SoftwareMember2022-09-300001280784htgc:SeniorSecuredDebtMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2020-12-310001280784htgc:CapitalInExcessOfParValueMember2021-07-012021-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:HibercellIncMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:XFourPharmaceuticalsIncMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-09-300001280784us-gaap:IncomeApproachValuationTechniqueMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784us-gaap:SeriesEPreferredStockMemberhtgc:MedroboticsCorporationMemberhtgc:WarrantInvestmentMemberhtgc:MedicalDevicesAndEquipmentMember2021-01-012021-12-310001280784htgc:EquityInvestmentsMemberhtgc:SingleStoreIncMemberhtgc:SoftwareMember2021-12-310001280784htgc:IncludedInCostMember2022-09-300001280784htgc:FirstLienIpMemberus-gaap:SalesRevenueNetMemberhtgc:CollateralTypeConcentrationRiskMember2021-01-012021-12-310001280784htgc:January2027NotesMember2022-09-300001280784htgc:June20253YearNotesMember2022-06-232022-06-230001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:ProventionBioIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:EnGeneIncMemberhtgc:ExitFeeMember2022-09-300001280784htgc:SBADebenturesIssuedOnAugustTwentyTwoThousandAndTwentyOneMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:TecturaCorporationMember2021-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:LocusBiosciencesIncMember2021-12-310001280784htgc:MUFGBankFacilityMember2021-12-310001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMemberhtgc:ZimperiumIncMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:TricidaIncMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2021-12-310001280784htgc:GelesisIncMemberhtgc:EquityInvestmentsMemberhtgc:MedicalDevicesAndEquipmentMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:UberTechnologiesIncMemberhtgc:EquityInvestmentsMemberus-gaap:CommonStockMember2021-01-012021-12-310001280784htgc:TwoThousandTwentyTwoConvertibleNotesMember2021-01-012021-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:MajorityOwnedControlInvestmentsMember2021-01-012021-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:VeemIncorporationMemberhtgc:SeniorsecuredtrancheaMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784us-gaap:SubsequentEventMemberhtgc:SupplementalDividendMember2022-11-172022-11-170001280784us-gaap:FairValueInputsLevel3Memberus-gaap:EstimateOfFairValueFairValueDisclosureMember2021-12-310001280784htgc:MeasurementInputsProbabilityWeightingOfAlternativeOutcomesMembersrt:MinimumMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CostApproachValuationTechniqueMemberhtgc:SustainableAndRenewableTechnologyMember2021-12-310001280784us-gaap:PreferredStockMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2021-01-012021-09-300001280784htgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputHypotheticalMarketYieldMembersrt:WeightedAverageMemberhtgc:MarketComparableCompaniesMemberhtgc:LowerMiddleMarketMember2021-12-310001280784us-gaap:FairValueInputsLevel3Memberhtgc:SBADebenturesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:AppliedGeneticTechnologiesCorporationMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:ExitFeeMember2022-09-300001280784htgc:MeasurementInputPremiumDiscountMemberhtgc:TechnologyMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberhtgc:MarketComparableCompaniesMember2022-09-300001280784us-gaap:RestrictedStockMemberus-gaap:CommonStockMember2022-07-012022-09-300001280784htgc:MyovantSciencesLtdMemberhtgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:InternetConsumerAndBusinessServicesMemberhtgc:ThumbtackIncorporationMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:DeferredFeesMember2022-09-300001280784us-gaap:EmployeeStockOptionMember2021-01-012021-09-300001280784us-gaap:GeographicConcentrationRiskMemberus-gaap:SalesRevenueNetMembercountry:CA2021-01-012021-12-310001280784htgc:OtherMember2022-09-300001280784htgc:CommunicationsAndNetworkingMemberhtgc:WarrantInvestmentMember2021-12-310001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:PhathomPharmaceuticalsIncMember2022-01-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:SeriesThreePreferredStockMemberhtgc:WarrantInvestmentMemberhtgc:EnGeneIncMember2022-01-012022-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:ADMABiologicsIncMember2021-12-310001280784htgc:PharmaceuticalsMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Memberhtgc:MeasurementInputHypotheticalMarketYieldMembersrt:WeightedAverageMemberhtgc:MarketComparableCompaniesMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:KazooIncPKYouEarnedItIncMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsUnderOneYearMaturityMember2022-09-300001280784htgc:SurgicalDevicesMember2022-09-300001280784htgc:OneMonthLIBORMember2022-09-300001280784htgc:PineappleEnergyLLCMemberhtgc:SeniorSecuredDebtMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMemberhtgc:SustainableAndRenewableTechnologyMember2022-09-300001280784htgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2022-09-300001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:ThumbtackIncorporationMemberhtgc:WarrantInvestmentMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:DebtInvestmentsMemberhtgc:LocusRoboticsCorporationMember2022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:ThreeGTMSLLCMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784us-gaap:RestrictedStockMember2021-07-012021-09-300001280784htgc:DrugDiscoveryAndDevelopmentMemberhtgc:EquityInvestmentsMemberhtgc:AveoPharmaceuticalsIncMemberus-gaap:CommonStockMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberus-gaap-supplement:InvestmentAffiliatedIssuerControlledMemberhtgc:SeniorsecuredtranchecMemberhtgc:OtherControlInvestmentsMemberhtgc:TecturaCorporationMember2021-12-310001280784htgc:InternetConsumerAndBusinessServicesMemberhtgc:WarrantInvestmentMemberhtgc:HouzzIncorporationMemberus-gaap:CommonStockMember2022-01-012022-09-300001280784htgc:EnmarkSystemsIncorporationMemberhtgc:DebtInvestmentsMember2022-09-300001280784us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2021-01-012021-09-300001280784htgc:MarchTwoThousandTwentySixBNotesMemberus-gaap:EstimateOfFairValueFairValueDisclosureMember2022-09-300001280784us-gaap-supplement:InvestmentAffiliatedIssuerControlledMember2022-07-012022-09-300001280784htgc:SeniorSecuredDebtMemberhtgc:BrainCorporationMemberhtgc:SoftwareMemberhtgc:DebtInvestmentsOneToFiveYearsMaturityMember2021-12-310001280784htgc:WarrantInvestmentMemberus-gaap:CommonStockMemberhtgc:SoftwareMemberhtgc:MixpanelIncMember2021-01-012021-12-310001280784htgc:IndustrySubSectorConcentrationRiskMemberus-gaap:SalesRevenueNetMemberhtgc:MedicalDevicesAndEquipmentMember2021-01-012021-12-310001280784htgc:MeasurementInputPremiumDiscountMemberhtgc:PharmaceuticalsMemberhtgc:DebtInvestmentMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMember