Residential Whole Loans - Fair Value (Details) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) loan	Dec. 31, 2015 USD ($) loan
Mortgage Loans on Real Estate [Line Items]
Outstanding principal balance \| $	$ 966,276	$ 786,330
Aggregate fair value \| $	$ 814,682	$ 623,276
Residential whole loans
Mortgage Loans on Real Estate [Line Items]
Number of loans \| loan	7,038
Residential whole loans \| Estimated fair value
Mortgage Loans on Real Estate [Line Items]
Number of loans \| loan	3,812	3,143

Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Acquired During Period At Acquisition At Fair Value Excluding Unsettled Purchases

No definition available.

+ Details

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- Definition

Residential whole loans at fair value outstanding principal balance

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Indicates the number of mortgages under each classification.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29.3)
-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section S99
-Paragraph 6
-Subparagraph (SX 210.5-04.(c) Schedule IV)
-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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