Quarterly report pursuant to Section 13 or 15(d)

Equity Method Investment in Affiliate - Additional Information (Detail)

v2.4.1.9
Equity Method Investment in Affiliate - Additional Information (Detail) (USD $)
3 Months Ended
Mar. 31, 2015
Oct. 31, 2014
Schedule of Equity Method Investments [Line Items]    
Loss from equity method investment in affiliate $ (53,000)us-gaap_IncomeLossFromEquityMethodInvestments  
Strong Upwind Holdings LLC [Member]    
Schedule of Equity Method Investments [Line Items]    
Project investment amount   144,000,000us-gaap_InvestmentOwnedAtCost
/ dei_LegalEntityAxis
= hasi_StrongUpwindHoldingsLlcMember
Loss from equity method investment in affiliate $ 100,000us-gaap_IncomeLossFromEquityMethodInvestments
/ dei_LegalEntityAxis
= hasi_StrongUpwindHoldingsLlcMember