Principles of Consolidation - Schedule of Unconsolidated VIEs Sponsored by Redwood (Details) - USD ($) $ in Thousands			12 Months Ended
		Mar. 31, 2026	Dec. 31, 2025
On-balance sheet assets, at fair value:
Subordinate securities, classified as AFS		$ 294,250	$ 287,557
Interest-only, senior and subordinate securities, classified as trading		182,137	135,459
Mortgage servicing rights	[1]	299,696	302,230
Commitment To Fund Residential Bridge Loan
On-balance sheet assets, at fair value:
Funding commitment		4,100,000	35,000
Payments for other commitments		20,000	20,000
Additional funding commitments		15,000	15,000
Variable Interest Entity, Not Primary Beneficiary
On-balance sheet assets, at fair value:
Strategic investments, equity method		10,123	10,263
Funding commitment		14,815	35,000
Maximum loss exposure		364,279	374,803
Variable Interest Entity, Not Primary Beneficiary | Subordinate securities, classified as AFS
On-balance sheet assets, at fair value:
Subordinate securities, classified as AFS		290,276	283,768
Interest-only, senior and subordinate securities, classified as trading | Variable Interest Entity, Not Primary Beneficiary
On-balance sheet assets, at fair value:
Interest-only, senior and subordinate securities, classified as trading		36,262	33,743
Mortgage servicing rights | Variable Interest Entity, Not Primary Beneficiary
On-balance sheet assets, at fair value:
Mortgage servicing rights		$ 12,803	$ 12,029

[1] Our consolidated balance sheets include assets of consolidated variable interest entities (“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 March 31, 2026 and December 31, 2025, assets of consolidated VIEs totaled $22,076,415 and $18,927,094, respectively. At March 31, 2026 and December 31, 2025, liabilities of consolidated VIEs totaled $20,784,429 and $17,850,175, respectively. See Note 16 for further discussion.