Quarterly report pursuant to Section 13 or 15(d)

Long-term Debt - Schedule of Outstanding Non-Recourse Asset-Backed Debt and Bank Loans (Details)

v3.8.0.1
Long-term Debt - Schedule of Outstanding Non-Recourse Asset-Backed Debt and Bank Loans (Details) - USD ($)
$ in Millions
Mar. 31, 2018
Dec. 31, 2017
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Debt issuance costs $ (26)  
Total non-recourse debt 1,215  
Value of Assets Pledged, Other 27 $ 29
Asset-Backed Non-recourse Debt [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Other non-recourse debt 109 90
Debt issuance costs (26) (27)
Total non-recourse debt 1,215 1,211
Anticipated Balance at Maturity 19  
Value of Assets Pledged, Receivables 176 162
Asset-Backed Non-recourse Debt [Member] | HASI Sustainable Yield Bond 2013-1 [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Outstanding Balance $ 67 67
Interest Rate 2.79%  
Anticipated Balance at Maturity $ 57  
Value of Assets Pledged, Receivables 86 86
Asset-Backed Non-recourse Debt [Member] | ABS Loan Agreement [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Outstanding Balance $ 80 81
Interest Rate 5.74%  
Anticipated Balance at Maturity $ 17  
Value of Assets Pledged, Other 75 79
Asset-Backed Non-recourse Debt [Member] | HASI Sustainable Yield Bond 2015-1A [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Outstanding Balance $ 93 94
Interest Rate 4.28%  
Anticipated Balance at Maturity $ 0  
Value of Assets Pledged, Receivables 136 137
Asset-Backed Non-recourse Debt [Member] | HASI Sustainable Yield Bond 2015-1B Note [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Outstanding Balance $ 14 14
Debt Instrument, Interest Rate, Effective Percentage 5.41%  
Interest Rate 5.00%  
Anticipated Balance at Maturity $ 0  
Value of Assets Pledged, Other 136 137
Asset-Backed Non-recourse Debt [Member] | 2017 Credit Agreement [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Outstanding Balance $ 165 180
Interest Rate 4.12%  
Anticipated Balance at Maturity $ 0  
Value of Assets Pledged, Other 202 226
Asset-Backed Non-recourse Debt [Member] | HASI SYB Loan Agreement 2015-2 [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Outstanding Balance $ 34 36
Interest Rate 6.39%  
Anticipated Balance at Maturity $ 0  
Value of Assets Pledged, Other 65 68
Asset-Backed Non-recourse Debt [Member] | HASI SYB Loan Agreement 2015-3 [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Outstanding Balance $ 141 143
Interest Rate 4.92%  
Anticipated Balance at Maturity $ 127  
Value of Assets Pledged, Receivables 169 171
Asset-Backed Non-recourse Debt [Member] | HASI SYB Loan Agreement 2016-1 [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Outstanding Balance $ 120 121
Interest Rate 4.83%  
Anticipated Balance at Maturity $ 106  
Value of Assets Pledged, Receivables 142 143
Asset-Backed Non-recourse Debt [Member] | HASI SYB Trust 2016-2 [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Outstanding Balance $ 82 81
Interest Rate 4.35%  
Anticipated Balance at Maturity $ 0  
Value of Assets Pledged, Receivables 86 86
Asset-Backed Non-recourse Debt [Member] | 2017 Master Repurchase Agreement [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Outstanding Balance $ 41 35
Interest Rate 3.99%  
Anticipated Balance at Maturity $ 36  
Value of Assets Pledged, Receivables 44 38
Asset-Backed Non-recourse Debt [Member] | HASI ECON 101 Trust [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Outstanding Balance $ 134 134
Interest Rate 3.57%  
Anticipated Balance at Maturity $ 0  
Value of Assets Pledged, Receivables 139 140
Asset-Backed Non-recourse Debt [Member] | HASI SYB Trust 2017-1 [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Outstanding Balance $ 161 162
Interest Rate 3.86%  
Anticipated Balance at Maturity $ 0  
Value of Assets Pledged, Receivables $ 208 $ 209
Other Non-recourse Debt [Member] | Minimum [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Interest Rate 2.26%  
Other Non-recourse Debt [Member] | Maximum [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Interest Rate 7.45%