Commitments and Contingencies - Narrative (Details) $ in Thousands		3 Months Ended			12 Months Ended
		Sep. 30, 2025 USD ($)	Mar. 31, 2024 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2025 USD ($) lease	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Loss Contingencies [Line Items]
Lessee, number of leases | lease					8
Present value of remaining lease payments					$ 11,706
Operating lease expense					4,000	$ 5,000	$ 5,000
Unamortized leasehold improvements					1,000
Leasehold amortization expense					$ 500	500	500
Lessee, number of office leases | lease					3
Operating lease term of contract					1 year
Operating lease liabilities					$ 10,666	$ 11,028
Operating Lease, Liability, Statement of Financial Position [Extensible List]					Accounts Payable and Accrued Liabilities	Accounts Payable and Accrued Liabilities
Operating lease right-of-use assets					$ 8,902	$ 9,167
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]					Other assets	Other assets
Weighted average remaining lease term					3 years
Discount rate (as a percent)					5.80%
Contingent liability	[1]				$ 28,150	$ 23,660
Net market valuation adjustments					43,016	$ 108,422	$ 35,814
CPP Joint Venture, Residential Investor Bridge and Term Loans
Loss Contingencies [Line Items]
Equity method investments, commitment amount			$ 140,000
Payments to acquire equity method investment					42,000
Oaktree Joint Venture, Residential Investor Bridge and Term Loans
Loss Contingencies [Line Items]
Equity method investments, commitment amount				$ 19,000
Payments to acquire equity method investment					5,000
Commitment To Fund Residential Investor Bridge Loan
Loss Contingencies [Line Items]
Funding commitment					258,000
Contingent liability					100
Net market valuation adjustments					800
Commitment To Fund Residential Investor Bridge Loan | Corporate Joint Venture
Loss Contingencies [Line Items]
Funding commitment					92,000
Commitment To Fund Legacy Residential Bridge Loans
Loss Contingencies [Line Items]
Funding commitment		$ 35,000			35,000
Payments for other commitments		10,000			10,000
Additional funding commitments		$ 25,000			$ 25,000

[1] Our consolidated balance sheets include assets of VIEs that can only be used to settle obligations of these VIEs and liabilities of consolidated VIEs for which creditors do not have recourse to Redwood Trust, Inc. or its affiliates. At December 31, 2025 and 2024, assets of consolidated VIEs totaled $18,927,094 and $14,654,942, respectively. At December 31, 2025 and 2024, liabilities of consolidated VIEs totaled $17,850,175 and $13,620,239, respectively. See Note 15 for further discussion.