Hannon Armstrong 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

Securitization of Receivables - Schedule of Fair Values of Retained Interests, Discount Rates Used in Valuing Interests (Detail)

v2.4.0.8

Securitization of Receivables - Schedule of Fair Values of Retained Interests, Discount Rates Used in Valuing Interests (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Minimum [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Discount rate	8.00%
Maximum [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Discount rate	10.00%
Servicing [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Amortized cost basis	$ 1,290	$ 1,592
Fair value	1,434	1,690
Weighted-average life in years	8 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	266	307
10% change in discount rate	437	505
Residual Assets [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Amortized cost basis	4,288	4,366
Fair value	4,220	4,639
Fair value that would be decreased based on hypothetical adverse changes in discount rates:
5% change in discount rate	1,128	1,220
10% change in discount rate	$ 1,751	$ 1,884
Residual Assets [Member] \| Minimum [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Weighted-average life in years	6 years	6 years
Discount rate	8.00%	8.00%
Residual Assets [Member] \| Maximum [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Weighted-average life in years	19 years	17 years
Discount rate	10.00%	10.00%

- Definition

Retained Interest Amortized Cost Basis

+ References

No definition available.

+ Details

Name:	hasi_RetainedInterestAmortizedCostBasis
Namespace Prefix:	hasi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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

Name:	hasi_SensitivityAnalysisOfFairValueOfInterestsContinuedToBeHeldByTransferorServicingAssetsOrLiabilitiesImpactOfFivePercentAdverseChangeInDiscountRate
Namespace Prefix:	hasi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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)

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

+ Details

Name:	us-gaap_AssumptionForFairValueOfAssetsOrLiabilitiesThatRelateToTransferorsContinuingInvolvementWeightedAverageLife1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_FairValueConcentrationOfRiskFinancialStatementCaptionsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueInputsDiscountRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_InterestsContinuedToBeHeldByTransferorInFinancialAssetsThatItHasSecuritizedOrServicingAssetsOrLiabilitiesRelatingToAssetsThatItHasSecuritizedAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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

+ Details

Name:	us-gaap_RetainedInterestFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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

+ Details

Name:	us-gaap_SensitivityAnalysisOfFairValueOfInterestsContinuedToBeHeldByTransferorServicingAssetsOrLiabilitiesImpactOf10PercentAdverseChangeInDiscountRate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant