Repurchase Agreements (Details 3) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Credit Suisse
Repurchase agreements counterparty risk
Amount at Risk	$ 584,602
Weighted Average Months to Maturity for Repurchase Agreements	1 month
Percent of Stockholders’ Equity	18.30%
Wells Fargo
Repurchase agreements counterparty risk
Amount at Risk	345,058
Weighted Average Months to Maturity for Repurchase Agreements	5 months
Percent of Stockholders’ Equity	10.80%
Wells Fargo Bank
Repurchase agreements counterparty risk
Amount at Risk	277,500
Wells Fargo Securities LLC
Repurchase agreements counterparty risk
Amount at Risk	67,600
UBS
Repurchase agreements counterparty risk
Amount at Risk	213,955
Weighted Average Months to Maturity for Repurchase Agreements	13 months
Percent of Stockholders’ Equity	6.70%
RBC
Repurchase agreements counterparty risk
Amount at Risk	192,999
Weighted Average Months to Maturity for Repurchase Agreements	4 months
Percent of Stockholders’ Equity	6.00%
Royal Bank of Canada
Repurchase agreements counterparty risk
Amount at Risk	182,700
RBC Capital Markets LLC
Repurchase agreements counterparty risk
Amount at Risk	10,300
RBS
Repurchase agreements counterparty risk
Amount at Risk	$ 167,317
Weighted Average Months to Maturity for Repurchase Agreements	1 month
Percent of Stockholders’ Equity	5.20%

Represents the minimum percentage of stockholders' equity at risk with respect to repurchase agreements with any single counterparty.

No definition available.

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- Definition

The amount at risk under repurchase agreements is defined as the excess of carrying amount (or market value, if higher than the carrying amount or if there is no carrying amount) of the securities or other assets sold under agreement to repurchase, including accrued interest plus any cash or other assets on deposit to secure the repurchase obligation, over the amount of the repurchase liability (adjusted for accrued interest).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph m

-Subparagraph 1

-Article 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(m)(1)(i)(B)(iii))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Weighted average maturity (weighted by amount of the agreement) of repurchase agreements with the counterparty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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