Collateral Positions (Details 2) $ in Thousands	Sep. 30, 2016 USD ($)
Collateral Positions
Total Fair Value of Assets Pledged and Accrued Interest	$ 10,721,720
Agency MBS
Collateral Positions
Total Fair Value of Assets Pledged and Accrued Interest	3,793,050
Legacy Non-Agency MBS
Collateral Positions
Total Fair Value of Assets Pledged and Accrued Interest	2,554,553
3 Year Step-up Securities
Collateral Positions
Total Fair Value of Assets Pledged and Accrued Interest	2,525,068
U.S. Treasuries
Collateral Positions
Total Fair Value of Assets Pledged and Accrued Interest	506,182
CRT securities
Collateral Positions
Total Fair Value of Assets Pledged and Accrued Interest	321,049
Residential Whole Loans
Collateral Positions
Total Fair Value of Assets Pledged and Accrued Interest	899,162
Cash
Collateral Positions
Total Fair Value of Assets Pledged and Accrued Interest	122,656
Repurchase Agreements and Other Advances
Collateral Positions
Fair Value	10,549,032
Amortized Cost	9,958,895
Accrued Interest on Pledged Assets	22,663
Repurchase Agreements and Other Advances \| Agency MBS
Collateral Positions
Fair Value	3,749,444
Amortized Cost	3,706,053
Accrued Interest on Pledged Assets	9,068
Repurchase Agreements and Other Advances \| Agency MBS \| FHLB Advances
Collateral Positions
Fair Value	227,500
Amortized Cost	224,100
Accrued Interest on Pledged Assets	590
Repurchase Agreements and Other Advances \| Legacy Non-Agency MBS
Collateral Positions
Fair Value	2,545,212
Amortized Cost	2,030,320
Accrued Interest on Pledged Assets	9,341
Non-Agency MBS acquired from consolidated VIEs in connection with resecuritization transactions	186,400
Non-Agency MBS pledged as collateral in connection with contemporaneous repurchase and reverse repurchase agreements entered into with a single counterparty	691,100
Repurchase Agreements and Other Advances \| 3 Year Step-up Securities
Collateral Positions
Fair Value	2,523,227
Amortized Cost	2,515,488
Accrued Interest on Pledged Assets	1,841
Repurchase Agreements and Other Advances \| U.S. Treasuries
Collateral Positions
Fair Value	506,182
Amortized Cost	506,182
Accrued Interest on Pledged Assets	0
Repurchase Agreements and Other Advances \| CRT securities
Collateral Positions
Fair Value	320,852
Amortized Cost	301,848
Accrued Interest on Pledged Assets	197
Repurchase Agreements and Other Advances \| Residential Whole Loans
Collateral Positions
Fair Value	896,946
Amortized Cost	891,835
Accrued Interest on Pledged Assets	2,216
Repurchase Agreements and Other Advances \| Cash
Collateral Positions
Fair Value	7,169
Amortized Cost	7,169
Accrued Interest on Pledged Assets	0
Derivative Hedging Instruments
Collateral Positions
Fair Value	149,956
Amortized Cost	149,990
Accrued Interest on Pledged Assets	69
Derivative Hedging Instruments \| Agency MBS
Collateral Positions
Fair Value	34,469
Amortized Cost	34,503
Accrued Interest on Pledged Assets	69
Derivative Hedging Instruments \| Legacy Non-Agency MBS
Collateral Positions
Fair Value	0
Amortized Cost	0
Accrued Interest on Pledged Assets	0
Derivative Hedging Instruments \| 3 Year Step-up Securities
Collateral Positions
Fair Value	0
Amortized Cost	0
Accrued Interest on Pledged Assets	0
Derivative Hedging Instruments \| U.S. Treasuries
Collateral Positions
Fair Value	0
Amortized Cost	0
Accrued Interest on Pledged Assets	0
Derivative Hedging Instruments \| CRT securities
Collateral Positions
Fair Value	0
Amortized Cost	0
Accrued Interest on Pledged Assets	0
Derivative Hedging Instruments \| Residential Whole Loans
Collateral Positions
Fair Value	0
Amortized Cost	0
Accrued Interest on Pledged Assets	0
Derivative Hedging Instruments \| Cash
Collateral Positions
Fair Value	115,487
Amortized Cost	115,487
Accrued Interest on Pledged Assets	0
Carrying Value \| Repurchase Agreements and Other Advances \| Residential Whole Loans
Collateral Positions
Fair Value	278,500
Amortized Cost	273,400
Total Fair Value of Assets Pledged and Accrued Interest	$ 618,400

Represents the amount of interest receivable on securities pledged as collateral.

No definition available.

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- Definition

-- None. No documentation exists for this element. --

+ References

No definition available.

+ Details

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- Definition

For an unclassified balance sheet, represents investments in debt and equity securities, categorized neither as held-to-maturity nor trading, which are acquired from a consolidated variable interest entity and eliminated on the entity's consolidated balance sheet.

+ References

No definition available.

+ Details

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- Definition

Represents the non-agency MBS pledged as collateral in connection with contemporaneous repurchase and reverse repurchase agreements entered into with a single counterparty.

+ References

No definition available.

+ Details

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- Definition

Sum of the fair values as of the date of the latest financial statement presented of securities pledged as collateral and the amount of interest receivable on the securities pledged as collateral.

+ References

No definition available.

+ Details

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- Definition

Represents the cost of debt and equity securities pledged as collateral, 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.

+ References

No definition available.

+ Details

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- Definition

Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=64858031&loc=SL6224234-111729

+ Details

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