Real Estate Securities - Gross Realized Gains and Losses on Sales and Calls of Available for Sale Securities (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Schedule of Available-for-sale Securities [Line Items]
Gross realized gains	$ 5,956	$ 992	$ 10,262	$ 992
Gross realized losses	0	0	0	0
Total Realized Gains on Sales and Calls of AFS Securities, Net	6,316	992	10,622	1,979
Call Option
Schedule of Available-for-sale Securities [Line Items]
Gross realized gains	360	0	360	987
Gross realized losses	$ 0	$ 0	$ 0	$ 0

This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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