Financings - Borrowings under Repurchase Agreements-Risk by Counterparty (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($)
Credit Suisse AG, Cayman Islands Branch
Amounts of collateral at risk under its repurchase agreements greater than 10% of the Company's equity with any counterparty
Amount of Collateral at Risk, at fair value	$ 143,835
Weighted Average Remaining Maturity (days)	782 days
Percentage of Stockholders’ Equity	78.90%
Barclays Capital Inc.
Amounts of collateral at risk under its repurchase agreements greater than 10% of the Company's equity with any counterparty
Amount of Collateral at Risk, at fair value	$ 42,491
Weighted Average Remaining Maturity (days)	24 days
Percentage of Stockholders’ Equity	23.30%
Nomura Securities International, Inc.
Amounts of collateral at risk under its repurchase agreements greater than 10% of the Company's equity with any counterparty
Amount of Collateral at Risk, at fair value	$ 31,848
Weighted Average Remaining Maturity (days)	28 days
Percentage of Stockholders’ Equity	17.50%
JP Morgan Securities LLC
Amounts of collateral at risk under its repurchase agreements greater than 10% of the Company's equity with any counterparty
Amount of Collateral at Risk, at fair value	$ 29,526
Weighted Average Remaining Maturity (days)	23 days
Percentage of Stockholders’ Equity	16.20%

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://fasb.org/us-gaap/role/ref/legacyRef
-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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