Derivative Instruments Schedule of Derivatves (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Financial derivatives–assets, at fair value	$ 1,732	$ 4,180
Financial derivatives–liabilities, at fair value	(20,234)	(2,047)
Derivative, Fair Value, Net	(18,502)	2,133
TBA securities- purchase contracts [Member]
Derivative [Line Items]
Derivative, Fair Value, Net	655	(23)
TBA securities- sale contracts [Member]
Derivative [Line Items]
Derivative, Fair Value, Net	(3,455)	(159)
Derivative Financial Instruments, Assets [Member] \| TBA securities- purchase contracts [Member]
Derivative [Line Items]
Financial derivatives–assets, at fair value	655	48
Derivative Financial Instruments, Assets [Member] \| TBA securities- sale contracts [Member]
Derivative [Line Items]
Financial derivatives–assets, at fair value	127	74
Derivative Financial Instruments, Liabilities [Member] \| TBA securities- purchase contracts [Member]
Derivative [Line Items]
Financial derivatives–liabilities, at fair value	0	(71)
Derivative Financial Instruments, Liabilities [Member] \| TBA securities- sale contracts [Member]
Derivative [Line Items]
Financial derivatives–liabilities, at fair value	(3,582)	(233)
Derivative Financial Instruments, Liabilities [Member] \| Futures [Member]
Derivative [Line Items]
Financial derivatives–liabilities, at fair value	(3,700)	(96)
Short [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Derivative, Fair Value, Net	(12,837)	1,911
Short [Member] \| Derivative Financial Instruments, Assets [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Financial derivatives–assets, at fair value	0	3,543
Short [Member] \| Derivative Financial Instruments, Liabilities [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Financial derivatives–liabilities, at fair value	(12,837)	(1,632)
Long [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Derivative, Fair Value, Net	504	66
Long [Member] \| Derivative Financial Instruments, Assets [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Financial derivatives–assets, at fair value	619	81
Long [Member] \| Derivative Financial Instruments, Assets [Member] \| Futures [Member]
Derivative [Line Items]
Financial derivatives–assets, at fair value	331	434
Long [Member] \| Derivative Financial Instruments, Liabilities [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Financial derivatives–liabilities, at fair value	$ (115)	$ (15)

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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