Fair Value Measurements - Financial Assets and Liabilities Carried at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Assets:
Non-Agency RMBS, at fair value	$ 1,064,169	$ 1,043,806
Agency MBS, at fair value	519,218	102,484
Loans held for investment, at fair value	11,196,678	11,397,046
Net Amounts Offset in the Consolidated Statements of Financial Position	117	0
Liabilities:
Securitized debt at fair value, collateralized by Loans held for investment	6,984,495	7,601,881
Net Amounts Offset in the Consolidated Statements of Financial Position	0	0
Fair Value, Measurements, Recurring
Assets:
Non-Agency RMBS, at fair value	1,064,169	1,043,806
Agency MBS, at fair value	519,218	102,484
Loans held for investment, at fair value	11,196,678	11,397,046
Counterparty and Cash Collateral, netting	(7,146)	(18,817)
Net Amounts Offset in the Consolidated Statements of Financial Position	117	0
Liabilities:
Secured Financing Agreements, at fair value	319,456	350,238
Securitized debt at fair value, collateralized by Loans held for investment	6,984,495	7,601,881
Counterparty and Cash Collateral, netting	0	0
Net Amounts Offset in the Consolidated Statements of Financial Position	0	0
Fair Value, Measurements, Recurring | Level 1
Assets:
Non-Agency RMBS, at fair value	0	0
Agency MBS, at fair value	0	0
Loans held for investment, at fair value	0	0
Derivatives, at fair value	117	0
Liabilities:
Secured Financing Agreements, at fair value	0	0
Securitized debt at fair value, collateralized by Loans held for investment	0	0
Derivatives, at fair value	0	0
Fair Value, Measurements, Recurring | Level 2
Assets:
Non-Agency RMBS, at fair value	0	0
Agency MBS, at fair value	519,218	102,484
Loans held for investment, at fair value	337,833	271,994
Derivatives, at fair value	7,146	18,817
Liabilities:
Secured Financing Agreements, at fair value	319,456	350,238
Securitized debt at fair value, collateralized by Loans held for investment	0	0
Derivatives, at fair value	0	0
Fair Value, Measurements, Recurring | Level 3
Assets:
Non-Agency RMBS, at fair value	1,064,169	1,043,806
Agency MBS, at fair value	0	0
Loans held for investment, at fair value	10,858,845	11,125,052
Derivatives, at fair value	0	0
Liabilities:
Secured Financing Agreements, at fair value	0	0
Securitized debt at fair value, collateralized by Loans held for investment	6,984,495	7,601,881
Derivatives, at fair value	$ 0	$ 0