Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	$ 193,850	$ (18,966)	$ (14,492)	$ (234,616)
TBAs [Member] | Gain (loss) on other derivative instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	(227,668)	(17,125)	(535,946)	(173,254)
Futures [Member] | Gain (loss) on other derivative instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	392,044	3,026	509,451	(63,851)
Options on U.S. Treasury Futures [Member] | Gain (loss) on other derivative instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	0	0	(2,224)	0
Interest Rate Swap [Member] | Long [Member] | Gain (loss) on interest rate swap and swaption agreements
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	100,435	7,019	772,829	64,313
Interest Rate Swap [Member] | Short [Member] | Gain (loss) on interest rate swap and swaption agreements
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	(75,055)	(15,316)	(756,744)	(67,460)
Interest Rate Swaption [Member] | Gain (loss) on interest rate swap and swaption agreements
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	9,426	4,350	13,414	8,249
Inverse Interest-Only Securities [Member] | Gain (loss) on other derivative instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	$ (5,332)	$ (920)	$ (15,272)	$ (2,613)