Real Estate Securities - Components of Carrying Value (Which Equals Fair Value) of Residential Available for Sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Carrying Value	$ 574,788	$ 572,752
Senior Securities
Schedule of Available-for-sale Securities [Line Items]
Carrying Value	137,209	136,546
Re-REMIC
Schedule of Available-for-sale Securities [Line Items]
Carrying Value	73,730	85,479
Subordinate Securities
Schedule of Available-for-sale Securities [Line Items]
Carrying Value	363,849	350,727
Residential
Schedule of Available-for-sale Securities [Line Items]
Principal balance	704,317	700,829
Credit reserve	(49,226)	(47,473)
Unamortized discount, net	(196,931)	(198,112)
Amortized cost	458,160	455,244
Gross unrealized gains	119,308	120,677
Gross unrealized losses	(2,680)	(3,169)
Carrying Value	574,788	572,752
Residential \| Senior Securities
Schedule of Available-for-sale Securities [Line Items]
Principal balance	144,676	148,862
Credit reserve	(4,521)	(4,814)
Unamortized discount, net	(38,156)	(41,877)
Amortized cost	101,999	102,171
Gross unrealized gains	37,078	36,304
Gross unrealized losses	(1,868)	(1,929)
Carrying Value	137,209	136,546
Residential \| Re-REMIC
Schedule of Available-for-sale Securities [Line Items]
Principal balance	81,935	95,608
Credit reserve	(5,609)	(6,857)
Unamortized discount, net	(16,507)	(19,613)
Amortized cost	59,819	69,138
Gross unrealized gains	13,911	16,341
Gross unrealized losses	0	0
Carrying Value	73,730	85,479
Residential \| Subordinate Securities
Schedule of Available-for-sale Securities [Line Items]
Principal balance	477,706	456,359
Credit reserve	(39,096)	(35,802)
Unamortized discount, net	(142,268)	(136,622)
Amortized cost	296,342	283,935
Gross unrealized gains	68,319	68,032
Gross unrealized losses	(812)	(1,240)
Carrying Value	$ 363,849	$ 350,727

Balance of credit reserve on available-for-sale securities.

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Available For Sale Securities Principal Balance

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Balance of net unamortized discount on available-for-sale securities.

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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-Publisher FASB
-Name Accounting Standards Codification
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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
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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.

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