Borrowings under Repurchase Agreements (Details 3) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2013
JP Morgan Securities LLC
Amounts at risk under its repurchase agreements greater than 10% of the Company's equity with any counterparty
Amounts at Risk, at fair value	$ 60,869
Weighted Average Remaining Maturity	14 days
Percentage of Stockholders' Equity (as a percent)	14.20%
Credit Suisse Securities (USA) LLC
Amounts at risk under its repurchase agreements greater than 10% of the Company's equity with any counterparty
Amounts at Risk, at fair value	54,903
Weighted Average Remaining Maturity	13 days
Percentage of Stockholders' Equity (as a percent)	13.00%
Barclays Capital Inc.
Amounts at risk under its repurchase agreements greater than 10% of the Company's equity with any counterparty
Amounts at Risk, at fair value	$ 43,573
Weighted Average Remaining Maturity	38 days
Percentage of Stockholders' Equity (as a percent)	10.30%

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).

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=6881521&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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- Definition

Represents the amount outstanding under the repurchase agreement as a percentage of stockholders' equity with a specific counterparty.

+ References

No definition available.

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