Derivatives - Gain (loss) on Derivative Instruments , Net (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Derivative [Line Items]
Gain on derivative instruments, net	$ 116,012	$ 106,412	$ 48,745	$ 326,623
Interest rate swaptions
Derivative [Line Items]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	0	26,502	0	51,940
Options on U.S. Treasury futures
Derivative [Line Items]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	(1,211)	0	(5,468)	0
Short position \| U.S. Treasury futures
Derivative [Line Items]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	171,219	150,475	64,846	439,408
Long position \| TBA securities
Derivative [Line Items]
Gain (Loss) on Derivative Instruments Held for Trading Purposes, Net	$ (53,996)	$ (70,565)	$ (10,633)	$ (164,725)

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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Aggregate net gain and losses (whether realized or unrealized) on all derivative instruments held for trading purposes whether or not settled physically.

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Amount of gain (loss) included in earnings for the period from the increase (decrease) in fair value of interest rate derivatives not designated as hedging instruments.

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