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

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

v3.19.1

Long-term Debt - Schedule of Outstanding Non-Recourse Asset-Backed Debt and Bank Loans (Footnotes) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Collateral Pledged [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Restricted cash	$ 42	$ 35
Asset-Backed Non-recourse Debt [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Total collateral pledged against our nonrecourse debt	$ 1,041	$ 1,105
HASI SYB Loan Agreement 2015-2 [Member] \| Interest Rate Swap [Member] \| Asset-Backed Non-recourse Debt [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Derivative rate	2.55%
2017 Master Repurchase Agreement [Member] \| Interest Rate Swap [Member] \| Asset-Backed Non-recourse Debt [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Derivative rate	2.42%

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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-Name Accounting Standards Codification
-Topic 942
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