Segment Information - Schedule of Business Segment Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026		Mar. 31, 2025	Dec. 31, 2025	[1]
Segment Reporting Information [Line Items]
Interest income	$ 356,919		$ 272,094
Interest expense	(322,202)		(244,152)
Net Interest Income	34,717		27,942
Non-Interest Income
Mortgage banking activities, net, excluding risk management derivatives	63,346		15,211
Risk management derivatives (losses) gains, net	(31,382)		17,842
Total Mortgage banking activities, net	31,964		33,053
Investment fair value changes, net	(23,199)		(5,188)
HEI income, net	7,109		10,166
Servicing income, net	8,021		3,407
Fee income (loss), net	2,886		2,351
Other income, net	2,437		1,550
Realized gains, net	0		567
Total non-interest income, net	29,218		45,906
General and administrative expenses	(49,358)		(37,471)
Portfolio management costs	(8,729)		(6,491)
Loan acquisition costs	(6,729)		(3,568)
Other expenses	(7,125)		(3,909)
Benefit from (Provision for) income taxes	2,503		(6,262)
Net Income (Loss)	(5,503)		16,147
Dividends on preferred stock	(1,750)		(1,750)
Net (Loss) Income Available (Related) To Common Stockholders	(7,253)		14,397
Total Assets	26,815,797	[1]	19,871,775	$ 23,701,114
Investment fair value changes, net, excluding risk management derivatives
Non-Interest Income
Investment fair value changes, net	15,075		(25,819)
Risk management derivatives gains (losses), net
Non-Interest Income
Investment fair value changes, net	(38,274)		20,631
Sequoia
Non-Interest Income
Total Mortgage banking activities, net	22,051		21,918
Aspire
Non-Interest Income
Total Mortgage banking activities, net	2,684		233
CoreVest
Non-Interest Income
Total Mortgage banking activities, net	7,229		10,902
Operating Segments | Sequoia
Segment Reporting Information [Line Items]
Interest income	61,306		31,639
Interest expense	(36,337)		(17,017)
Net Interest Income	24,969		14,622
Non-Interest Income
Mortgage banking activities, net, excluding risk management derivatives	57,962		1,131
Risk management derivatives (losses) gains, net	(35,911)		20,787
Total Mortgage banking activities, net	22,051		21,918
Investment fair value changes, net	0		0
HEI income, net	0		0
Servicing income, net	0		0
Fee income (loss), net	0		0
Other income, net	0		0
Realized gains, net	0		0
Total non-interest income, net	22,051		21,918
General and administrative expenses	(7,049)		(5,418)
Portfolio management costs	0		0
Loan acquisition costs	(2,841)		(1,071)
Other expenses	0		0
Benefit from (Provision for) income taxes	1,245		(7,191)
Net Income (Loss)	38,375		22,860
Dividends on preferred stock	(544)		(406)
Net (Loss) Income Available (Related) To Common Stockholders	37,831		22,454
Total Assets	2,573,719		1,543,436
Operating Segments | Sequoia | Investment fair value changes, net, excluding risk management derivatives
Non-Interest Income
Investment fair value changes, net	0		0
Operating Segments | Sequoia | Risk management derivatives gains (losses), net
Non-Interest Income
Investment fair value changes, net	0		0
Operating Segments | Aspire
Segment Reporting Information [Line Items]
Interest income	18,408		44
Interest expense	(14,766)		(227)
Net Interest Income	3,642		(183)
Non-Interest Income
Mortgage banking activities, net, excluding risk management derivatives	(1,544)		233
Risk management derivatives (losses) gains, net	4,228		0
Total Mortgage banking activities, net	2,684		233
Investment fair value changes, net	0		0
HEI income, net	0		0
Servicing income, net	0		0
Fee income (loss), net	0		0
Other income, net	0		0
Realized gains, net	0		0
Total non-interest income, net	2,684		233
General and administrative expenses	(2,466)		(928)
Portfolio management costs	0		0
Loan acquisition costs	(1,046)		0
Other expenses	0		0
Benefit from (Provision for) income taxes	(342)		(70)
Net Income (Loss)	2,472		(948)
Dividends on preferred stock	(204)		(17)
Net (Loss) Income Available (Related) To Common Stockholders	2,268		(965)
Total Assets	891,538		15,681
Operating Segments | Aspire | Investment fair value changes, net, excluding risk management derivatives
Non-Interest Income
Investment fair value changes, net	0		0
Operating Segments | Aspire | Risk management derivatives gains (losses), net
Non-Interest Income
Investment fair value changes, net	0		0
Operating Segments | CoreVest
Segment Reporting Information [Line Items]
Interest income	4,192		4,394
Interest expense	(2,083)		(3,011)
Net Interest Income	2,109		1,383
Non-Interest Income
Mortgage banking activities, net, excluding risk management derivatives	6,928		13,847
Risk management derivatives (losses) gains, net	301		(2,945)
Total Mortgage banking activities, net	7,229		10,902
Investment fair value changes, net	(265)		0
HEI income, net	0		0
Servicing income, net	0		0
Fee income (loss), net	2,827		3,079
Other income, net	589		0
Realized gains, net	0		0
Total non-interest income, net	10,380		13,981
General and administrative expenses	(12,988)		(9,958)
Portfolio management costs	0		0
Loan acquisition costs	(2,842)		(2,497)
Other expenses	(2,010)		(2,202)
Benefit from (Provision for) income taxes	2,061		648
Net Income (Loss)	(3,290)		1,355
Dividends on preferred stock	(87)		(67)
Net (Loss) Income Available (Related) To Common Stockholders	(3,377)		1,288
Total Assets	329,333		343,985
Operating Segments | CoreVest | Investment fair value changes, net, excluding risk management derivatives
Non-Interest Income
Investment fair value changes, net	(265)		0
Operating Segments | CoreVest | Risk management derivatives gains (losses), net
Non-Interest Income
Investment fair value changes, net	0		0
Operating Segments | Redwood Investments
Segment Reporting Information [Line Items]
Interest income	268,748		201,570
Interest expense	(256,306)		(185,046)
Net Interest Income	12,442		16,524
Non-Interest Income
Mortgage banking activities, net, excluding risk management derivatives	0		0
Risk management derivatives (losses) gains, net	0		0
Total Mortgage banking activities, net	0		0
Investment fair value changes, net	(15,443)		3,543
HEI income, net	575		55
Servicing income, net	8,021		3,407
Fee income (loss), net	192		142
Other income, net	898		507
Realized gains, net	0		567
Total non-interest income, net	(5,757)		8,221
General and administrative expenses	(3,384)		(1,870)
Portfolio management costs	(4,155)		(2,060)
Loan acquisition costs	0		0
Other expenses	(5,115)		(1,707)
Benefit from (Provision for) income taxes	(1,373)		304
Net Income (Loss)	(7,342)		19,412
Dividends on preferred stock	(658)		(552)
Net (Loss) Income Available (Related) To Common Stockholders	(8,000)		18,860
Total Assets	21,903,485		14,514,702
Operating Segments | Redwood Investments | Investment fair value changes, net, excluding risk management derivatives
Non-Interest Income
Investment fair value changes, net	22,815		(22,748)
Operating Segments | Redwood Investments | Risk management derivatives gains (losses), net
Non-Interest Income
Investment fair value changes, net	(38,258)		26,291
Operating Segments | Legacy Investments
Segment Reporting Information [Line Items]
Interest income	4,000		34,151
Interest expense	(12,710)		(38,851)
Net Interest Income	(8,710)		(4,700)
Non-Interest Income
Mortgage banking activities, net, excluding risk management derivatives	0		0
Risk management derivatives (losses) gains, net	0		0
Total Mortgage banking activities, net	0		0
Investment fair value changes, net	(7,491)		(8,731)
HEI income, net	6,534		10,111
Servicing income, net	0		0
Fee income (loss), net	(133)		(870)
Other income, net	950		0
Realized gains, net	0		0
Total non-interest income, net	(140)		510
General and administrative expenses	(16)		(16)
Portfolio management costs	(4,547)		(4,431)
Loan acquisition costs	0		0
Other expenses	0		0
Benefit from (Provision for) income taxes	610		0
Net Income (Loss)	(12,803)		(8,637)
Dividends on preferred stock	(257)		(708)
Net (Loss) Income Available (Related) To Common Stockholders	(13,060)		(9,345)
Total Assets	945,021		3,087,249
Operating Segments | Legacy Investments | Investment fair value changes, net, excluding risk management derivatives
Non-Interest Income
Investment fair value changes, net	(7,475)		(3,071)
Operating Segments | Legacy Investments | Risk management derivatives gains (losses), net
Non-Interest Income
Investment fair value changes, net	(16)		(5,660)
Corporate/ Other
Segment Reporting Information [Line Items]
Interest income	265		296
Interest expense	0		0
Net Interest Income	265		296
Non-Interest Income
Mortgage banking activities, net, excluding risk management derivatives	0		0
Risk management derivatives (losses) gains, net	0		0
Total Mortgage banking activities, net	0		0
Investment fair value changes, net	0		0
HEI income, net	0		0
Servicing income, net	0		0
Fee income (loss), net	0		0
Other income, net	0		1,043
Realized gains, net	0		0
Total non-interest income, net	0		1,043
General and administrative expenses	(23,455)		(19,281)
Portfolio management costs	(27)		0
Loan acquisition costs	0		0
Other expenses	0		0
Benefit from (Provision for) income taxes	302		47
Net Income (Loss)	(22,915)		(17,895)
Dividends on preferred stock	0		0
Net (Loss) Income Available (Related) To Common Stockholders	(22,915)		(17,895)
Total Assets	172,701		366,722
Corporate/ Other | Investment fair value changes, net, excluding risk management derivatives
Non-Interest Income
Investment fair value changes, net	0		0
Corporate/ Other | Risk management derivatives gains (losses), net
Non-Interest Income
Investment fair value changes, net	$ 0		$ 0

[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.