Investment Securities - AFS and Fair Value Option (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Dec. 31, 2015
RMBS
Unrealized Losses
Portion of securities with variable rate	$ 159,400
RMBS \| Available-for-sale
Investment Securities
Maximum investment in available-for-sale securities with aggregate expected modified durations of less than 12 months (as a percent)	10.00%
Cost of third party management	$ 400
Estimated Fair Value
Securities with a loss less than 12 months	15,466	$ 17,026
Securities with a loss greater than 12 months	643	653
Unrealized Losses
Securities with a loss less than 12 months	(191)	(180)
Securities with a loss greater than 12 months	(144)	(160)
Portion of securities with variable rate		$ 122,700
CMBS \| Fair value option
Unrealized Losses
Unpaid principal balance of investment securities before consolidation of VIEs	4,600,000
Purchases in which fair value option was elected	46,600
Purchase amount reflected as repayment of debt of consolidated VIEs	13,400
CMBS, fair value option
Unrealized Losses
Portion of securities with variable rate	$ 0

Represents the cost to execute trading of available-for-sale securities by a third party manager engaged by the entity.

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- Definition

Represents the unpaid principal balance of the investment securities before consolidation of the VIEs.

+ References

No definition available.

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Represents the amount of investment securities bearing variable interest rates.

+ References

No definition available.

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- Definition

Represents the maximum percentage of assets invested in a category of available-for-sale securities that is allocated for securities with expected modified durations of less than twelve months in the aggregate.

+ References

No definition available.

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- Definition

The cash outflow to acquire investment securities for which the fair value option was elected, including the amount reflected as repayment of debt of consolidated VIEs.

+ References

No definition available.

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- Definition

Amount of purchases of investment securities for which the fair value option was elected, that is reflected as repayment of debt of consolidated VIEs.

+ References

No definition available.

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- Definition

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.

+ References

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
-Paragraph 7
-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 that have been in a continuous loss position for less than twelve months.

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- Definition

This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

+ 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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
-Paragraph 6
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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+ References

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)(1)
-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
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

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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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