Quarterly report pursuant to Section 13 or 15(d)

The Company - Additional Information (Detail)

v2.4.1.9
The Company - Additional Information (Detail) (USD $)
 1 Months Ended 3 Months Ended 1 Months Ended 12 Months Ended
May 31, 2014
acre
Mar. 31, 2015
Mar. 31, 2014
Oct. 31, 2014
State
Project
Dec. 31, 2014
Organization [Line Items]          
Acquisition date   May 28, 2014      
Business combination consideration paid $ 106,700,000us-gaap_BusinessCombinationConsiderationTransferred1        
Acquisition completed date   Jan. 01, 2013      
Area of land acquired 12,500hasi_AreaOfLandAcquired        
Acquisition related costs 2,500,000us-gaap_BusinessCombinationAcquisitionRelatedCosts        
Liabilities assumed in connection with acquisitions 0us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities        
Rental Income   2,088,000us-gaap_OperatingLeasesIncomeStatementLeaseRevenue      
Interest Income, Financing receivables   8,328,000us-gaap_InterestIncomeOperating 4,618,000us-gaap_InterestIncomeOperating    
Strong Upwind Holdings LLC [Member]          
Organization [Line Items]          
Project investment amount       144,000,000us-gaap_InvestmentOwnedAtCost
/ dei_LegalEntityAxis
= hasi_StrongUpwindHoldingsLlcMember 		 
Number of limited liability companies       4hasi_NumberOfLimitedLiabilityCompanies
/ dei_LegalEntityAxis
= hasi_StrongUpwindHoldingsLlcMember 		 
Number of States       5hasi_NumberOfStates
/ dei_LegalEntityAxis
= hasi_StrongUpwindHoldingsLlcMember 		 
Strong Upwind Holdings LLC [Member] | Minimum [Member]          
Organization [Line Items]          
Ownership interest based on voting percentages       4.00%hasi_OwnershipInterestPercentageBasedOnVotingInterest
/ dei_LegalEntityAxis
= hasi_StrongUpwindHoldingsLlcMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember 		 
Strong Upwind Holdings LLC [Member] | Maximum [Member]          
Organization [Line Items]          
Ownership interest based on voting percentages       17.50%hasi_OwnershipInterestPercentageBasedOnVotingInterest
/ dei_LegalEntityAxis
= hasi_StrongUpwindHoldingsLlcMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember 		 
Strong Upwind Holdings LLC [Member] | Wind Project Investment [Member]          
Organization [Line Items]          
Number of operating projects       10hasi_NumberOfOperatingProjects
/ us-gaap_FinancialInstrumentAxis
= hasi_WindProjectInvestmentMember
/ dei_LegalEntityAxis
= hasi_StrongUpwindHoldingsLlcMember 		 
AWCC [Member]          
Organization [Line Items]          
Business combination consideration paid 19,400,000us-gaap_BusinessCombinationConsiderationTransferred1
/ us-gaap_BusinessAcquisitionAxis
= hasi_AwccMember 		       
Working capital adjustment         200,000hasi_BusinessCombinationWorkingCapitalAdjustment
/ us-gaap_BusinessAcquisitionAxis
= hasi_AwccMember
Rental Income   2,100,000us-gaap_OperatingLeasesIncomeStatementLeaseRevenue
/ us-gaap_BusinessAcquisitionAxis
= hasi_AwccMember 		     
Interest Income, Financing receivables   $ 600,000us-gaap_InterestIncomeOperating
/ us-gaap_BusinessAcquisitionAxis
= hasi_AwccMember 		     
Solar [Member]          
Organization [Line Items]          
Number of projects 20hasi_NumberOfProjects
/ us-gaap_BusinessAcquisitionAxis
= hasi_SolarMember 		       
Wind [Member]          
Organization [Line Items]          
Number of projects 57hasi_NumberOfProjects
/ us-gaap_BusinessAcquisitionAxis
= hasi_WindMember