Investment Securities Available For Sale - Unrealized Losses in OCI (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Agency RMBS
Schedule of Available-for-sale Securities [Line Items]
Carrying Value Less Than 12 Months	$ 71,587	$ 0
Gross Unrealized Losses Less Than 12 Months	(688)	0
Carrying Value Greater Than 12 Months	476,157	638,936
Gross Unrealized Losses Greater Than 12 Months	(14,497)	(12,597)
Carrying Value Total	547,744	638,936
Gross Unrealized Losses Total	(15,185)	(12,597)
Non-Agency RMBS
Schedule of Available-for-sale Securities [Line Items]
Carrying Value Less Than 12 Months	771	0
Gross Unrealized Losses Less Than 12 Months	0	0
Carrying Value Greater Than 12 Months	796	967
Gross Unrealized Losses Greater Than 12 Months	(211)	(191)
Carrying Value Total	1,567	967
Gross Unrealized Losses Total	(211)	(191)
Total investment securities available for sale
Schedule of Available-for-sale Securities [Line Items]
Carrying Value Less Than 12 Months	72,358	0
Gross Unrealized Losses Less Than 12 Months	(688)	0
Carrying Value Greater Than 12 Months	476,953	639,903
Gross Unrealized Losses Greater Than 12 Months	(14,708)	(12,788)
Carrying Value Total	549,311	639,903
Gross Unrealized Losses Total	(15,396)	(12,788)
Investment Held in Securitization Trust
Schedule of Available-for-sale Securities [Line Items]
Carrying Value Less Than 12 Months	0	0
Gross Unrealized Losses Less Than 12 Months	0	0
Carrying Value Greater Than 12 Months	0	0
Gross Unrealized Losses Greater Than 12 Months	0	0
Carrying Value Total	0	0
Gross Unrealized Losses Total	0	0
CMBS
Schedule of Available-for-sale Securities [Line Items]
Carrying Value Less Than 12 Months	0	0
Gross Unrealized Losses Less Than 12 Months	0	0
Carrying Value Greater Than 12 Months	0	0
Gross Unrealized Losses Greater Than 12 Months	0	0
Carrying Value Total	0	0
Gross Unrealized Losses Total	$ 0	$ 0

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 320
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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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