Residential Whole Loans - Realized Credit Losses Net of Recoveries (Details) - Residential whole loans - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Realized credit losses, net of recoveries	$ (4,373)	$ (3,731)
Non-QM loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Realized credit losses, net of recoveries	(151)	(137)
Business purpose loans \| Single-family rental loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Realized credit losses, net of recoveries	(27)	(1,196)
Business purpose loans \| Single-family transitional loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Realized credit losses, net of recoveries	(3,325)	(2,173)
Business purpose loans \| Multifamily transitional loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Realized credit losses, net of recoveries	(347)	(169)
Legacy RPL/NPL loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Realized credit losses, net of recoveries	(523)	(56)
Other loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Realized credit losses, net of recoveries	$ 0	$ 0