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

Equity - Additional Information (Detail)

v3.3.0.814

Equity - Additional Information (Detail) - 2013 Plan [Member] - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Restricted Common Stock [Member] \| Employees and Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded			196,517
Restricted common shares vesting years			Vest in 2015 to 2019
Restricted Common Stock [Member] \| Certain Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded			390,131
Restricted Incentive [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense	$ 2.7	$ 1.7	$ 7.7	$ 3.6
Unrecognized compensation expense	$ 11.8		$ 11.8
Weighted-average term in which unrecognized compensation expense is expected to be recognized			2 years
Assumed forfeiture rate for calculation of equity-based compensation expense			5.00%

- Definition

Expected Forfeiture Rate In Determining Share Based Compensation Expense

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- Definition

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- Definition

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- Definition

Costs and payments related to employee benefits and equity-based compensation, such as pension expense and contributions, other postretirement benefits expense and payments, stock or unit options expense, and amortization of restricted stock or unit.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

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Unrecognized cost of unvested share-based compensation awards.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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- Definition

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- Definition

Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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