Mortgage-Backed Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Investments [Line Items]
Unrealized gain on investments, net	$ 142,469	$ 192,874	$ 286,118	$ 80,873
Residential Mortgage Backed Securities [Member] | Agency MBS
Investments [Line Items]
Unrealized loss on debt securities	139,842	191,786	278,204	78,405
Commercial Mortgage Backed Securities [Member] | Agency MBS
Investments [Line Items]
Unrealized loss on debt securities	2,410	0	6,785	1,073
Interest-Only-Strip [Member]
Investments [Line Items]
Unrealized loss on debt securities	223	1,066	1,148	1,222
Asset-backed Securities, Securitized Loans and Receivables
Investments [Line Items]
Unrealized gain (loss) on other investments	$ (6)	$ 22	$ (19)	$ 173