Annual report pursuant to Section 13 and 15(d)

Securitization of Receivables - Additional Information (Detail)

v2.4.1.9
Securitization of Receivables - Additional Information (Detail) (USD $)
 3 Months Ended 12 Months Ended
Dec. 31, 2012
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Sep. 30, 2012
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]          
Gain on securitized financing receivables $ 2,500,000us-gaap_GainLossOnSecuritizationOfFinancialAssets $ 8,500,000us-gaap_GainLossOnSecuritizationOfFinancialAssets $ 5,600,000us-gaap_GainLossOnSecuritizationOfFinancialAssets   $ 3,900,000us-gaap_GainLossOnSecuritizationOfFinancialAssets
Managed receivables   2,500,000,000hasi_ReceivablesServiced 2,100,000,000hasi_ReceivablesServiced    
Securitization credit losses   0us-gaap_NetCreditLossOnLoansManagedOrSecuritizedOrAssetbackedFinancingArrangement 0us-gaap_NetCreditLossOnLoansManagedOrSecuritizedOrAssetbackedFinancingArrangement 0us-gaap_NetCreditLossOnLoansManagedOrSecuritizedOrAssetbackedFinancingArrangement  
Asset-backed Securities, Securitized Loans and Receivables [Member]          
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]          
Managed receivables   1,700,000,000hasi_ReceivablesServiced
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_AssetBackedSecuritiesSecuritizedLoansAndReceivablesMember 		1,600,000,000hasi_ReceivablesServiced
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_AssetBackedSecuritiesSecuritizedLoansAndReceivablesMember 		   
Residual Assets [Member]          
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]          
Residual assets   $ 5,200,000us-gaap_RetainedInterestFairValueDisclosure
/ us-gaap_FinancialInstrumentAxis
= hasi_ResidualAssetsMember 		$ 4,900,000us-gaap_RetainedInterestFairValueDisclosure
/ us-gaap_FinancialInstrumentAxis
= hasi_ResidualAssetsMember 		   
Minimum [Member]          
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]          
Annual servicing fees   0.05%hasi_ServicesFeeAnnualRate
/ us-gaap_RangeAxis
= us-gaap_MinimumMember 		     
Maximum [Member]          
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]          
Annual servicing fees   0.20%hasi_ServicesFeeAnnualRate
/ us-gaap_RangeAxis
= us-gaap_MaximumMember