Subsequent Events - Additional Information (Detail) - Subsequent Event $ / shares in Units, $ in Millions	Apr. 10, 2016 USD ($) $ / shares
7.625% Series E Cumulative Redeemable Preferred Stock
Subsequent Event [Line Items]
Preferred Stock, par value \| $ / shares	$ 0.01
Hatteras
Subsequent Event [Line Items]
Business combination consideration transferred \| $	$ 1,500.0
Percentage of aggregate consideration in common shares	65.00%
Percentage of aggregate consideration in cash	35.00%
Hatteras \| Atlantic Capital Advisors LLC
Subsequent Event [Line Items]
Termination Fee payable to ACA \| $	$ 45.4
Hatteras \| 7.625% Series A Cumulative Redeemable Preferred Stock
Subsequent Event [Line Items]
Preferred Stock, par value \| $ / shares	$ 0.001

Business Acquisition Percentage Of Aggregate Merger Consideration In Cash

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Business Acquisition Percentage Of Aggregate Merger Consideration In Stock

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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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 210.5-02.28)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29
-Article 5

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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