Financing Agreements - Pledged Collateral (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair value of securities pledged as collateral under financing agreements	$ 10,439,785	$ 10,170,472
Accrued interest	25,800	27,100
Securitized \| Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair value of securities pledged as collateral under financing agreements	7,052,710	6,913,710
Non-Mark-to-Market \| Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair value of securities pledged as collateral under financing agreements	562,959	740,260
Mark-to-Market \| Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair value of securities pledged as collateral under financing agreements	2,824,116	2,516,502
Residential whole loans \| Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair value of securities pledged as collateral under financing agreements	8,720,446	8,734,115
Residential whole loans \| Securitized \| Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair value of securities pledged as collateral under financing agreements	7,022,048	6,886,776
Residential whole loans \| Non-Mark-to-Market \| Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair value of securities pledged as collateral under financing agreements	562,959	740,260
Residential whole loans \| Mark-to-Market \| Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair value of securities pledged as collateral under financing agreements	1,135,439	1,107,079
Securities, at fair value \| Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair value of securities pledged as collateral under financing agreements	1,631,474	1,352,918
Securities, at fair value \| Securitized \| Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair value of securities pledged as collateral under financing agreements	0	0
Securities, at fair value \| Non-Mark-to-Market \| Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair value of securities pledged as collateral under financing agreements	0	0
Securities, at fair value \| Mark-to-Market \| Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair value of securities pledged as collateral under financing agreements	1,631,474	1,352,918
Other assets: REO \| Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair value of securities pledged as collateral under financing agreements	87,865	83,439
Other assets: REO \| Securitized \| Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair value of securities pledged as collateral under financing agreements	30,662	26,934
Other assets: REO \| Non-Mark-to-Market \| Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair value of securities pledged as collateral under financing agreements	0	0
Other assets: REO \| Mark-to-Market \| Asset Pledged as Collateral with Right
Debt Instrument [Line Items]
Fair value of securities pledged as collateral under financing agreements	57,203	56,505
Non-agency MBS \| Mark-to-Market
Debt Instrument [Line Items]
Fair value of securities pledged as collateral under financing agreements	495,900	506,600
Carrying value	$ 391,900	$ 394,900

Accrued Interest, Securities Sold Under Agreements To Repurchase

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