Real Estate Securities - Gross Realized Gains and Losses on Sales and Calls of Available for Sale Securities (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Schedule of Available-for-sale Securities [Line Items]
Total Realized Gains on Sales and Calls of AFS Securities, net	$ 1,734	$ 1,990	$ 9,561	$ 21,312
Sales
Schedule of Available-for-sale Securities [Line Items]
Gross realized gains	1,734	1,990	9,381	22,395
Gross realized losses	0	0	0	(2,293)
Calls
Schedule of Available-for-sale Securities [Line Items]
Gross realized gains	0	0	677	1,210
Gross realized losses	$ 0	$ 0	$ (497)	$ 0

Available-for-sale Securities, Gross Realized Gain (Loss) On Sales And Calls

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- Definition

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

+ References

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=73527792&loc=d3e27357-111563

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

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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