Hannon Armstrong Sustainable Infrastructure Capital, Inc. Annual report pursuant to Section 13 and 15(d)

Annual report pursuant to Section 13 and 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

Fair Value Measurements - Schedule of Fair Values of Retained Assets, Discount Rates Used in Valuing Assets (Detail)

v2.4.1.9

Fair Value Measurements - Schedule of Fair Values of Retained Assets, Discount Rates Used in Valuing Assets (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Servicing Assets at Fair Value [Line Items]
Discount rate	8.00%us-gaap_FairValueInputsDiscountRate
Servicing [Member]
Servicing Assets at Fair Value [Line Items]
Amortized cost basis	$ 1.0	$ 1.3
Fair value	1.2	1.4
Weighted-average life in years	9 years	8 years
Discount rate	8.00%	8.00%
Fair value that would be decreased based on hypothetical adverse changes in discount rates:
5% change in discount rate	0.2	0.3
10% change in discount rate	0.4	0.4
Residual Assets [Member]
Servicing Assets at Fair Value [Line Items]
Amortized cost basis	5.1	4.8
Fair value	5.2	4.9
Discount rate	8.00%
Fair value that would be decreased based on hypothetical adverse changes in discount rates:
5% change in discount rate	1.5	1.2
10% change in discount rate	$ 2.3	$ 1.8
Residual Assets [Member] \| Minimum [Member]
Servicing Assets at Fair Value [Line Items]
Weighted-average life in years	7 years	6 years
Discount rate		8.00%
Residual Assets [Member] \| Maximum [Member]
Servicing Assets at Fair Value [Line Items]
Weighted-average life in years	19 years	19 years
Discount rate		10.00%

- Definition

Retained Interest Amortized Cost Basis

+ References

No definition available.

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- Definition

Sensitivity Analysis Of Fair Value Of Interests Continued To Be Held By Transferor Servicing Assets Or Liabilities Impact Of Five Percent Adverse Change In Discount Rate

+ References

No definition available.

+ Details

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- Definition

Weighted average life of securitized assets regardless of when the transfer occurred, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)(2)

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

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- Definition

Fair value portion of interest continued to be held by a transferor after transferring financial assets to a third party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 10

-Section 15

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=7502516&loc=d3e94415-111705

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- Definition

The hypothetical financial impact of a 10 percent adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107314-111719

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