Mortgage-Backed Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Investments [Line Items]
Unrealized gain (loss) on investments, net	$ 192,874	$ (179,100)	$ 80,873	$ (121,491)
Residential Mortgage Backed Securities [Member] | Agency MBS
Investments [Line Items]
Unrealized loss on debt securities	191,786	(177,768)	78,405	(120,735)
Commercial Mortgage Backed Securities [Member] | Agency MBS
Investments [Line Items]
Unrealized loss on debt securities	0	(777)	1,073	(815)
Interest-Only-Strip [Member]
Investments [Line Items]
Unrealized loss on debt securities	1,066	(591)	1,222	36
Asset-backed Securities, Securitized Loans and Receivables
Investments [Line Items]
Unrealized gain (loss) on other investments	$ 22	$ 36	$ 173	$ 23