Principles of Consolidation - Assets and Liabilities of Consolidated Variable Interest Entity's (Details) $ in Thousands		Dec. 31, 2022 USD ($) investment		Dec. 31, 2021 USD ($) investment		Dec. 31, 2020 USD ($)
Variable Interest Entity [Line Items]
Home equity investments		$ 403,462		$ 192,740
Other investments	[1]	390,938		449,229
Cash and cash equivalents		258,894	[1]	450,485	[1]	$ 461,000
Restricted cash		70,470	[1]	80,999	[1]	$ 83,000
Accrued interest receivable		60,893		47,515
Other assets	[1]	211,240		231,117
Total Assets	[1]	13,030,899		14,706,944
Short-term debt	[1]	2,029,679		2,177,362
Accrued interest payable		46,612		39,297
Accrued expenses and other liabilities	[1]	180,203		245,788
Asset-backed securities issued	[1]	7,986,752		9,253,557
Total liabilities	[1]	$ 11,946,914		13,320,857
Securitizations that did not elect CFE | investment		2
CAFL
Variable Interest Entity [Line Items]
Fair value of securities owned		$ 304,000		302,000
Freddie Mac SLST
Variable Interest Entity [Line Items]
Fair value of securities owned		323,000		445,000
Business purpose loans, held-for-investment
Variable Interest Entity [Line Items]
Fair value of loans	[1]	4,968,513		4,432,680
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Total Assets		9,257,291		10,661,081
Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Home equity investments		132,627
Other investments		301,213		544,307
Cash and cash equivalents		13,475		6,481
Restricted cash		29,862		46,086
Accrued interest receivable		36,392		35,401
Other assets		25,397		41,826
Total Assets		9,257,291		10,661,081
Short-term debt		206,510		294,447
Accrued interest payable		25,300		25,018
Accrued expenses and other liabilities		51,714		46,325
Asset-backed securities issued		7,986,752		9,253,557
Total liabilities		8,270,276		9,619,347
Estimated fair value of investments		$ 979,267		$ 1,033,913
Number of VIEs | investment		64		60
Variable Interest Entity, Primary Beneficiary | Residential loans, held-for-investment | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		$ 4,832,407		$ 5,747,150
Variable Interest Entity, Primary Beneficiary | Business purpose loans, held-for-investment | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		3,461,367		3,766,316
Variable Interest Entity, Primary Beneficiary | Consolidated Agency multifamily loans | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		424,551		473,514
Variable Interest Entity, Primary Beneficiary | Legacy Sequoia | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Home equity investments		0
Other investments		0		0
Cash and cash equivalents		0		0
Restricted cash		69		148
Accrued interest receivable		284		210
Other assets		637		61
Total Assets		185,922		230,874
Short-term debt		0		0
Accrued interest payable		282		99
Accrued expenses and other liabilities		0		0
Asset-backed securities issued		184,191		227,881
Total liabilities		184,473		227,980
Estimated fair value of investments		$ 1,285		$ 2,634
Number of VIEs | investment		20		20
Variable Interest Entity, Primary Beneficiary | Legacy Sequoia | Residential loans, held-for-investment | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		$ 184,932		$ 230,455
Variable Interest Entity, Primary Beneficiary | Legacy Sequoia | Business purpose loans, held-for-investment | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0		0
Variable Interest Entity, Primary Beneficiary | Legacy Sequoia | Consolidated Agency multifamily loans | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0		0
Variable Interest Entity, Primary Beneficiary | Sequoia | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Home equity investments		0
Other investments		0		0
Cash and cash equivalents		0		0
Restricted cash		73		5
Accrued interest receivable		11,227		10,885
Other assets		0		0
Total Assets		3,201,717		3,639,355
Short-term debt		0		0
Accrued interest payable		8,880		8,452
Accrued expenses and other liabilities		81		5
Asset-backed securities issued		2,971,109		3,383,048
Total liabilities		2,980,070		3,391,505
Estimated fair value of investments		$ 219,299		$ 245,417
Number of VIEs | investment		17		16
Variable Interest Entity, Primary Beneficiary | Sequoia | Residential loans, held-for-investment | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		$ 3,190,417		$ 3,628,465
Variable Interest Entity, Primary Beneficiary | Sequoia | Business purpose loans, held-for-investment | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0		0
Variable Interest Entity, Primary Beneficiary | Sequoia | Consolidated Agency multifamily loans | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0		0
Variable Interest Entity, Primary Beneficiary | CAFL | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Home equity investments		0
Other investments		0		0
Cash and cash equivalents		710		0
Restricted cash		26,296		15,221
Accrued interest receivable		18,102		15,737
Other assets		14,265		32,510
Total Assets		3,520,740		3,829,784
Short-term debt		0		0
Accrued interest payable		10,918		11,030
Accrued expenses and other liabilities		4,559		1,171
Asset-backed securities issued		3,115,807		3,474,898
Total liabilities		3,131,284		3,487,099
Estimated fair value of investments		$ 385,927		$ 339,419
Number of VIEs | investment		19		16
Variable Interest Entity, Primary Beneficiary | CAFL | Residential loans, held-for-investment | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		$ 0		$ 0
Variable Interest Entity, Primary Beneficiary | CAFL | Business purpose loans, held-for-investment | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		3,461,367		3,766,316
Variable Interest Entity, Primary Beneficiary | CAFL | Consolidated Agency multifamily loans | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0		0
Variable Interest Entity, Primary Beneficiary | Freddie Mac SLST | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Home equity investments		0
Other investments		0		0
Cash and cash equivalents		0		0
Restricted cash		0		0
Accrued interest receivable		5,144		5,792
Other assets		2,898		2,028
Total Assets		1,465,100		1,896,050
Short-term debt		0		0
Accrued interest payable		3,561		4,055
Accrued expenses and other liabilities		0		0
Asset-backed securities issued		1,222,150		1,588,463
Total liabilities		1,225,711		1,592,518
Estimated fair value of investments		$ 237,807		$ 301,795
Number of VIEs | investment		3		3
Variable Interest Entity, Primary Beneficiary | Freddie Mac SLST | Residential loans, held-for-investment | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		$ 1,457,058		$ 1,888,230
Variable Interest Entity, Primary Beneficiary | Freddie Mac SLST | Business purpose loans, held-for-investment | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0		0
Variable Interest Entity, Primary Beneficiary | Freddie Mac SLST | Consolidated Agency multifamily loans | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0		0
Variable Interest Entity, Primary Beneficiary | Freddie Mac K-Series | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Home equity investments		0
Other investments		0		0
Cash and cash equivalents		0		0
Restricted cash		0		0
Accrued interest receivable		1,293		1,315
Other assets		0		0
Total Assets		425,844		474,829
Short-term debt		0		0
Accrued interest payable		1,167		1,190
Accrued expenses and other liabilities		0		0
Asset-backed securities issued		392,785		441,857
Total liabilities		393,952		443,047
Estimated fair value of investments		$ 31,767		$ 31,657
Number of VIEs | investment		1		1
Variable Interest Entity, Primary Beneficiary | Freddie Mac K-Series | Residential loans, held-for-investment | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		$ 0		$ 0
Variable Interest Entity, Primary Beneficiary | Freddie Mac K-Series | Business purpose loans, held-for-investment | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0		0
Variable Interest Entity, Primary Beneficiary | Freddie Mac K-Series | Consolidated Agency multifamily loans | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		424,551		473,514
Variable Interest Entity, Primary Beneficiary | Servicing Investment | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Home equity investments		0
Other investments		301,213		384,754
Cash and cash equivalents		12,765		6,481
Restricted cash		0		25,420
Accrued interest receivable		342		1,462
Other assets		7,547		7,177
Total Assets		321,867		425,294
Short-term debt		206,510		294,447
Accrued interest payable		492		192
Accrued expenses and other liabilities		24,745		28,115
Asset-backed securities issued		0		0
Total liabilities		231,747		322,754
Estimated fair value of investments		$ 90,120		$ 102,540
Number of VIEs | investment		3		3
Variable Interest Entity, Primary Beneficiary | Servicing Investment | Residential loans, held-for-investment | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		$ 0		$ 0
Variable Interest Entity, Primary Beneficiary | Servicing Investment | Business purpose loans, held-for-investment | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0		0
Variable Interest Entity, Primary Beneficiary | Servicing Investment | Consolidated Agency multifamily loans | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0		0
Variable Interest Entity, Primary Beneficiary | HEI | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Home equity investments		132,627
Other investments		0		159,553
Cash and cash equivalents		0		0
Restricted cash		3,424		5,292
Accrued interest receivable		0		0
Other assets		50		50
Total Assets		136,101		164,895
Short-term debt		0		0
Accrued interest payable		0		0
Accrued expenses and other liabilities		22,329		17,034
Asset-backed securities issued		100,710		137,410
Total liabilities		123,039		154,444
Estimated fair value of investments		$ 13,062		$ 10,451
Number of VIEs | investment		1		1
Fair value of securities owned		$ 13,000
Variable Interest Entity, Primary Beneficiary | HEI | Residential loans, held-for-investment | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0		$ 0
Variable Interest Entity, Primary Beneficiary | HEI | Business purpose loans, held-for-investment | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0		0
Variable Interest Entity, Primary Beneficiary | HEI | Consolidated Agency multifamily loans | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		$ 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 December 31, 2022 and 2021, assets of consolidated VIEs totaled $9,257,291 and $10,661,081, respectively. At December 31, 2022 and 2021, liabilities of consolidated VIEs totaled $8,270,276 and $9,619,347, respectively. See Note 4 for further discussion.