Segment Information - Schedule of Business Segment Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2025		Jun. 30, 2024	Jun. 30, 2025		Jun. 30, 2024	Dec. 31, 2024	[1]
Segment Reporting Information [Line Items]
Interest income	$ 284,336		$ 225,417	$ 556,430		$ 430,157
Interest expense	(270,502)		(200,124)	(514,654)		(380,654)
Net Interest Income	13,834		25,293	41,776		49,503
Non-Interest Income
Mortgage banking activities, net, excluding risk management derivatives	(7,278)		31,310	7,933		40,268
Risk management derivatives gains, net	48,135		(12,386)	65,977		(6,788)
Total Mortgage banking activities, net	40,857		18,924	73,910		33,480
Investment fair value changes, net	(84,704)		1,098	(89,892)		22,935
HEI income (loss), net	(12,899)		15,883	(2,733)		24,969
Servicing income, net	1,608		3,549	5,015		7,774
Fee income (loss), net	2,209		1,663	4,560		2,664
Other income (loss), net	352		1,037	1,902		262
Realized gains, net	640		0	1,207		409
Total non-interest (loss) income, net	(51,937)		42,154	(6,031)		92,493
General and administrative expenses	(36,983)		(33,284)	(74,454)		(67,853)
Portfolio management costs	(10,028)		(4,864)	(16,519)		(8,461)
Loan acquisition costs	(4,781)		(3,664)	(8,349)		(5,901)
Other expenses	(4,035)		(5,177)	(7,944)		(8,538)
(Provision for) benefit from income taxes	(4,562)		(4,924)	(10,824)		(5,447)
Net Income (Loss)	(98,492)		15,534	(82,345)		45,796
Total Assets	21,333,020	[1]	16,491,104	21,333,020	[1]	16,491,104	$ 18,258,344
Investment fair value changes, net, excluding risk management derivatives
Non-Interest Income
Investment fair value changes, net	(101,696)		(1,446)	(127,515)		16,010
Risk management derivatives gains (losses), net
Non-Interest Income
Investment fair value changes, net	16,992		2,544	37,623		6,925
Sequoia Mortgage Banking
Non-Interest Income
Total Mortgage banking activities, net	24,399		6,245	46,550		14,072
CoreVest Mortgage Banking
Non-Interest Income
Total Mortgage banking activities, net	16,458		12,679	27,360		19,408
Operating Segments | Sequoia Mortgage Banking
Segment Reporting Information [Line Items]
Interest income	37,021		21,097	68,704		35,409
Interest expense	(21,502)		(9,922)	(34,841)		(18,188)
Net Interest Income	15,519		11,175	33,863		17,221
Non-Interest Income
Mortgage banking activities, net, excluding risk management derivatives	(22,632)		18,264	(21,268)		23,002
Risk management derivatives gains, net	47,028		(12,019)	67,815		(8,930)
Total Mortgage banking activities, net	24,396		6,245	46,547		14,072
Investment fair value changes, net	0		0	0		0
HEI income (loss), net	0		0	0		0
Servicing income, net	0		0	0		0
Fee income (loss), net	0		0	0		0
Other income (loss), net	0		0	0		0
Realized gains, net	0		0	0		0
Total non-interest (loss) income, net	24,396		6,245	46,547		14,072
General and administrative expenses	(7,205)		(4,957)	(13,551)		(9,746)
Portfolio management costs	0		0	0		0
Loan acquisition costs	(1,267)		(980)	(2,338)		(1,551)
Other expenses	0		0	0		0
(Provision for) benefit from income taxes	(9,289)		(1,560)	(16,551)		(3,054)
Net Income (Loss)	22,154		9,923	47,970		16,942
Total Assets	1,689,117		1,106,416	1,689,117		1,106,416
Operating Segments | Sequoia Mortgage Banking | Investment fair value changes, net, excluding risk management derivatives
Non-Interest Income
Investment fair value changes, net	0		0	0		0
Operating Segments | Sequoia Mortgage Banking | Risk management derivatives gains (losses), net
Non-Interest Income
Investment fair value changes, net	0		0	0		0
Operating Segments | CoreVest Mortgage Banking
Segment Reporting Information [Line Items]
Interest income	3,737		7,008	8,131		10,779
Interest expense	(1,903)		(5,504)	(4,293)		(8,381)
Net Interest Income	1,834		1,504	3,838		2,398
Non-Interest Income
Mortgage banking activities, net, excluding risk management derivatives	15,354		13,046	29,201		17,266
Risk management derivatives gains, net	1,107		(367)	(1,838)		2,142
Total Mortgage banking activities, net	16,461		12,679	27,363		19,408
Investment fair value changes, net	0		0	0		0
HEI income (loss), net	0		0	0		0
Servicing income, net	0		0	0		0
Fee income (loss), net	2,782		1,174	5,861		1,800
Other income (loss), net	715		0	2,397		0
Realized gains, net	0		0	0		0
Total non-interest (loss) income, net	19,958		13,853	35,621		21,208
General and administrative expenses	(10,218)		(9,677)	(20,815)		(21,102)
Portfolio management costs	0		0	0		0
Loan acquisition costs	(3,514)		(2,433)	(6,011)		(4,097)
Other expenses	(2,203)		(2,203)	(4,405)		(5,008)
(Provision for) benefit from income taxes	278		(449)	927		1,687
Net Income (Loss)	6,135		595	9,155		(4,914)
Total Assets	301,743		371,980	301,743		371,980
Operating Segments | CoreVest Mortgage Banking | Investment fair value changes, net, excluding risk management derivatives
Non-Interest Income
Investment fair value changes, net	0		0	0		0
Operating Segments | CoreVest Mortgage Banking | Risk management derivatives gains (losses), net
Non-Interest Income
Investment fair value changes, net	0		0	0		0
Operating Segments | Redwood Investments
Segment Reporting Information [Line Items]
Interest income	219,744		155,045	421,313		294,818
Interest expense	(197,647)		(130,575)	(377,601)		(247,049)
Net Interest Income	22,097		24,470	43,712		47,769
Non-Interest Income
Mortgage banking activities, net, excluding risk management derivatives	0		0	0		0
Risk management derivatives gains, net	0		0	0		0
Total Mortgage banking activities, net	0		0	0		0
Investment fair value changes, net	(8,998)		17,083	(5,375)		40,637
HEI income (loss), net	126		0	181		0
Servicing income, net	1,608		3,549	5,015		7,774
Fee income (loss), net	412		428	554		733
Other income (loss), net	394		1,038	764		1,208
Realized gains, net	640		0	1,207		314
Total non-interest (loss) income, net	(5,818)		22,098	2,346		50,666
General and administrative expenses	(1,528)		(1,349)	(2,877)		(4,164)
Portfolio management costs	(2,594)		(1,201)	(4,654)		(2,210)
Loan acquisition costs	0		(13)	0		(14)
Other expenses	(1,832)		(2,974)	(3,539)		(3,530)
(Provision for) benefit from income taxes	1,567		(2,914)	1,871		(4,060)
Net Income (Loss)	11,892		38,117	36,859		84,457
Total Assets	15,982,357		11,420,075	15,982,357		11,420,075
Operating Segments | Redwood Investments | Investment fair value changes, net, excluding risk management derivatives
Non-Interest Income
Investment fair value changes, net	(26,958)		17,083	(49,626)		40,637
Operating Segments | Redwood Investments | Risk management derivatives gains (losses), net
Non-Interest Income
Investment fair value changes, net	17,960		0	44,251		0
Operating Segments | Legacy Investments
Segment Reporting Information [Line Items]
Interest income	23,449		41,697	57,601		86,822
Interest expense	(32,898)		(39,861)	(65,212)		(78,685)
Net Interest Income	(9,449)		1,836	(7,611)		8,137
Non-Interest Income
Mortgage banking activities, net, excluding risk management derivatives	0		0	0		0
Risk management derivatives gains, net	0		0	0		0
Total Mortgage banking activities, net	0		0	0		0
Investment fair value changes, net	(75,574)		(14,535)	(84,305)		(16,902)
HEI income (loss), net	(13,025)		15,883	(2,914)		24,969
Servicing income, net	0		0	0		0
Fee income (loss), net	(985)		61	(1,855)		131
Other income (loss), net	0		0	0		0
Realized gains, net	0		0	0		0
Total non-interest (loss) income, net	(89,584)		1,409	(89,074)		8,198
General and administrative expenses	(57)		(88)	(73)		(52)
Portfolio management costs	(7,434)		(3,642)	(11,865)		(6,225)
Loan acquisition costs	0		(238)	0		(239)
Other expenses	0		0	0		0
(Provision for) benefit from income taxes	2,535		0	2,535		0
Net Income (Loss)	(103,989)		(723)	(106,088)		9,819
Total Assets	2,953,731		3,230,928	2,953,731		3,230,928
Operating Segments | Legacy Investments | Investment fair value changes, net, excluding risk management derivatives
Non-Interest Income
Investment fair value changes, net	(74,606)		(17,079)	(77,677)		(23,827)
Operating Segments | Legacy Investments | Risk management derivatives gains (losses), net
Non-Interest Income
Investment fair value changes, net	(968)		2,544	(6,628)		6,925
Corporate/ Other
Segment Reporting Information [Line Items]
Interest income	385		570	681		2,329
Interest expense	(16,552)		(14,262)	(32,707)		(28,351)
Net Interest Income	(16,167)		(13,692)	(32,026)		(26,022)
Non-Interest Income
Mortgage banking activities, net, excluding risk management derivatives	0		0	0		0
Risk management derivatives gains, net	0		0	0		0
Total Mortgage banking activities, net	0		0	0		0
Investment fair value changes, net	(132)		(1,450)	(212)		(800)
HEI income (loss), net	0		0	0		0
Servicing income, net	0		0	0		0
Fee income (loss), net	0		0	0		0
Other income (loss), net	(757)		(1)	(1,259)		(946)
Realized gains, net	0		0	0		95
Total non-interest (loss) income, net	(889)		(1,451)	(1,471)		(1,651)
General and administrative expenses	(17,975)		(17,213)	(37,138)		(32,789)
Portfolio management costs	0		(21)	0		(26)
Loan acquisition costs	0		0	0		0
Other expenses	0		0	0		0
(Provision for) benefit from income taxes	347		(1)	394		(20)
Net Income (Loss)	(34,684)		(32,378)	(70,241)		(60,508)
Total Assets	406,072		361,705	406,072		361,705
Corporate/ Other | Investment fair value changes, net, excluding risk management derivatives
Non-Interest Income
Investment fair value changes, net	(132)		(1,450)	(212)		(800)
Corporate/ Other | Risk management derivatives gains (losses), net
Non-Interest Income
Investment fair value changes, net	$ 0		$ 0	$ 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 June 30, 2025 and December 31, 2024, assets of consolidated VIEs totaled $17,484,443 and $14,654,942, respectively. At June 30, 2025 and December 31, 2024, liabilities of consolidated VIEs totaled $16,386,516 and $13,620,239, respectively. See Note 16 for further discussion.