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)

v3.10.0.1

Long-term Debt - Additional Information (Details) $ / shares in Units, shares in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) $ / shares shares
Debt Instrument [Line Items]
Principal, net of issuance costs	$ 1,096,000,000		$ 1,096,000,000		$ 1,211,000,000
Total interest expense	19,681,000	$ 17,584,000	57,424,000	$ 46,728,000
Convertible Senior Notes [Member] \| 4.125% Convertible Senior Notes Due September 1, 2022 [Member]
Debt Instrument [Line Items]
Principal	150,000,000		150,000,000		150,000,000
Principal, net of issuance costs					$ 145,000,000
Interest rate					4.125%
Conversion rate of shares for each $1,000 principal amount of convertible notes					36.7107
Conversion of debt equals shares (in shares) \| shares					5.5
Conversion price per share (in usd per share) \| $ / shares					$ 27.24
Adjustment for dividends declared (in usd per share) \| $ / shares					$ 0.33
Redemption price, percentage					100.00%
Total interest expense	$ 2,000,000	$ 800,000	5,000,000	$ 800,000
Residential Solar Loan [Member] \| SunPower Corporation [Member]
Debt Instrument [Line Items]
Payment of principal and interest on loan			$ 1,000,000

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