Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	$ 38,809	$ (209,192)	$ (220,783)
TBAs [Member] | Gain (loss) on other derivative instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	(487,713)	(193,479)	60,798
Futures [Member] | Gain (loss) on other derivative instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	514,467	(49,213)	18,143
Options on TBAs [Member] | Gain (loss) on other derivative instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	0	(5,683)	0
Options on Futures [Member] | Gain (loss) on other derivative instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	(2,224)	0	0
Interest Rate Swap [Member] | Long [Member] | Gain (loss) on interest rate swap, cap and swaption agreements
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	772,829	92,317	(1,128,788)
Interest Rate Swap [Member] | Short [Member] | Gain (loss) on interest rate swap, cap and swaption agreements
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	(756,744)	(66,828)	879,289
Interest Rate Swaption [Member] | Gain (loss) on interest rate swap, cap and swaption agreements
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	13,414	16,602	(61,307)
Markit IOS Total Return Swap [Member] | Gain (loss) on other derivative instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	0	0	(2,430)
Inverse Interest-Only Securities [Member] | Gain (loss) on other derivative instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	$ (15,220)	$ (2,908)	$ 13,512