HA Sustainable Infrastructure Capital, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Long-term Debt - Additional Information (Details)

v3.8.0.1

Long-term Debt - Additional Information (Details) $ / shares in Units, shares in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2018 USD ($) debt_instrument	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($) $ / shares shares	Jan. 31, 2017 USD ($)
Debt Instrument [Line Items]
Aggregate principal amount	$ 1,214,612,000		$ 1,210,861,000
Principal, net of issuance costs	1,215,000,000
Total interest expense	18,711,000	$ 13,783,000
Asset-Backed Non-recourse Debt [Member]
Debt Instrument [Line Items]
Principal, net of issuance costs	1,215,000,000		$ 1,211,000,000
SunPower Corporation [Member] \| Residential Solar Loan [Member]
Debt Instrument [Line Items]
Payment of principal and interest on loan	$ 1,000,000
HASI Sustainable Yield Bond 2015-1 [Member] \| Asset-Backed Non-recourse Debt [Member]
Debt Instrument [Line Items]
Number of debt instruments \| debt_instrument	2
HASI Sustainable Yield Bond 2015-1A [Member] \| Asset-Backed Non-recourse Debt [Member]
Debt Instrument [Line Items]
Aggregate principal amount	$ 101,000,000
Interest rate	4.28%
HASI Sustainable Yield Bond 2015-1B [Member] \| Asset-Backed Non-recourse Debt [Member]
Debt Instrument [Line Items]
Aggregate principal amount	$ 18,000,000			$ 14,000,000
Interest rate	5.00%
4.125% Convertible Senior Notes Due September 1, 2022 [Member] \| Convertible Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate			4.125%
Principal	$ 150,000,000		$ 150,000,000
Principal, net of issuance costs			$ 145,000,000
Conversion rate of shares for each $1,000 principal amount of convertible notes			36.7107
Conversion price per share (in usd per share) \| $ / shares			$ 27.24
Conversion of debt equals shares \| shares			5.5
Adjustment for dividends declared (in usd per share) \| $ / shares			$ 0.33
Redemption price, percentage			100.00%
Total interest expense	$ 2,000,000

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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