Principles of Consolidation - Assets and Liabilities of Consolidated Variable Interest Entities Accounted for as Collateralized Financing Entities (Details) $ in Thousands		Mar. 31, 2022 USD ($) investment	Dec. 31, 2021 USD ($) investment
Variable Interest Entity [Line Items]
Other investments	[1]	$ 635,581	$ 641,969
Cash and cash equivalents	[1]	409,272	450,485
Restricted cash	[1]	73,549	80,999
Accrued interest receivable		48,717	47,515
Other assets	[1]	202,202	231,117
Total Assets	[1]	14,253,292	14,706,944
Short-term debt	[1]	1,647,246	2,177,362
Accrued interest payable		38,647	39,297
Accrued expenses and other liabilities	[1]	244,450	245,788
Asset-backed securities issued	[1]	8,872,366	9,253,557
Total liabilities	[1]	12,808,026	13,320,857
CAFL
Variable Interest Entity [Line Items]
Fair value of securities owned		306,000	302,000
Carrying value of securities owned		37,000	38,000
Freddie Mac SLST
Variable Interest Entity [Line Items]
Fair value of securities owned		437,000	445,000
Carrying value of securities owned		129,000	143,000
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Total Assets		10,250,802	10,661,081
Total liabilities		9,202,156	9,619,347
Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Other investments		489,529	544,307
Cash and cash equivalents		9,684	6,481
Restricted cash		37,668	46,086
Accrued interest receivable		34,877	35,401
Other assets		26,263	41,826
Total Assets		10,250,802	10,661,081
Short-term debt		253,393	294,447
Accrued interest payable		25,349	25,018
Accrued expenses and other liabilities		51,048	46,325
Asset-backed securities issued		8,872,366	9,253,557
Total liabilities		9,202,156	9,619,347
Value of our investments in VIEs(1)		$ 1,040,987	$ 1,033,913
Number of VIEs | investment		61	60
Residential loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		$ 5,870,067	$ 5,747,150
Business purpose loans, held-for-investment
Variable Interest Entity [Line Items]
Fair value of loans	[1]	4,248,889	4,432,680
Business purpose loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		3,330,910	3,766,316
Multifamily loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		451,804	473,514
Legacy Sequoia | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Other investments		0	0
Cash and cash equivalents		0	0
Restricted cash		148	148
Accrued interest receivable		194	210
Other assets		0	61
Total Assets		222,555	230,874
Short-term debt		0	0
Accrued interest payable		106	99
Accrued expenses and other liabilities		0	0
Asset-backed securities issued		220,301	227,881
Total liabilities		220,407	227,980
Value of our investments in VIEs(1)		$ 1,912	$ 2,634
Number of VIEs | investment		20	20
Legacy Sequoia | Residential loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		$ 222,213	$ 230,455
Legacy Sequoia | Business purpose loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0	0
Legacy Sequoia | Multifamily loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0	0
Sequoia | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Other investments		0	0
Cash and cash equivalents		0	0
Restricted cash		4	5
Accrued interest receivable		11,945	10,885
Other assets		0	0
Total Assets		3,884,265	3,639,355
Short-term debt		0	0
Accrued interest payable		9,598	8,452
Accrued expenses and other liabilities		4	5
Asset-backed securities issued		3,627,920	3,383,048
Total liabilities		3,637,522	3,391,505
Value of our investments in VIEs(1)		$ 244,396	$ 245,417
Number of VIEs | investment		17	16
Sequoia | Residential loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		$ 3,872,316	$ 3,628,465
Sequoia | Business purpose loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0	0
Sequoia | Multifamily loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0	0
CAFL | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Other investments		0	0
Cash and cash equivalents		0	0
Restricted cash		8,260	15,221
Accrued interest receivable		14,763	15,737
Other assets		16,229	32,510
Total Assets		3,370,162	3,829,784
Short-term debt		0	0
Accrued interest payable		10,342	11,030
Accrued expenses and other liabilities		1,386	1,171
Asset-backed securities issued		3,012,841	3,474,898
Total liabilities		3,024,569	3,487,099
Value of our investments in VIEs(1)		$ 342,343	$ 339,419
Number of VIEs | investment		16	16
CAFL | Residential loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		$ 0	$ 0
CAFL | Business purpose loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		3,330,910	3,766,316
CAFL | Multifamily loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0	0
Freddie Mac SLST | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Other investments		0	0
Cash and cash equivalents		0	0
Restricted cash		0	0
Accrued interest receivable		5,584	5,792
Other assets		2,421	2,028
Total Assets		1,783,543	1,896,050
Short-term debt		0	0
Accrued interest payable		3,888	4,055
Accrued expenses and other liabilities		0	0
Asset-backed securities issued		1,470,043	1,588,463
Total liabilities		1,473,931	1,592,518
Value of our investments in VIEs(1)		$ 307,916	$ 301,795
Number of VIEs | investment		3	3
Freddie Mac SLST | Residential loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		$ 1,775,538	$ 1,888,230
Freddie Mac SLST | Business purpose loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0	0
Freddie Mac SLST | Multifamily loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0	0
Freddie Mac K-Series | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Other investments		0	0
Cash and cash equivalents		0	0
Restricted cash		0	0
Accrued interest receivable		1,362	1,315
Other assets		0	0
Total Assets		453,166	474,829
Short-term debt		0	0
Accrued interest payable		1,232	1,190
Accrued expenses and other liabilities		0	0
Asset-backed securities issued		419,883	441,857
Total liabilities		421,115	443,047
Value of our investments in VIEs(1)		$ 31,921	$ 31,657
Number of VIEs | investment		1	1
Freddie Mac K-Series | Residential loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		$ 0	$ 0
Freddie Mac K-Series | Business purpose loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0	0
Freddie Mac K-Series | Multifamily loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		451,804	473,514
Servicing Investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Other investments		336,282	384,754
Cash and cash equivalents		9,684	6,481
Restricted cash		24,170	25,420
Accrued interest receivable		1,029	1,462
Other assets		7,563	7,177
Total Assets		378,728	425,294
Short-term debt		253,393	294,447
Accrued interest payable		183	192
Accrued expenses and other liabilities		26,406	28,115
Asset-backed securities issued		0	0
Total liabilities		279,982	322,754
Value of our investments in VIEs(1)		$ 98,746	$ 102,540
Number of VIEs | investment		3	3
Servicing Investment | Residential loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		$ 0	$ 0
Servicing Investment | Business purpose loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0	0
Servicing Investment | Multifamily loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0	0
HEI | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Other investments		153,247	159,553
Cash and cash equivalents		0	0
Restricted cash		5,086	5,292
Accrued interest receivable		0	0
Other assets		50	50
Total Assets		158,383	164,895
Short-term debt		0	0
Accrued interest payable		0	0
Accrued expenses and other liabilities		23,252	17,034
Asset-backed securities issued		121,378	137,410
Total liabilities		144,630	154,444
Value of our investments in VIEs(1)		$ 13,753	$ 10,451
Number of VIEs | investment		1	1
Fair value of securities owned		$ 14,000
HEI | Residential loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0	$ 0
HEI | Business purpose loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | Collateralized Financing Entities
Variable Interest Entity [Line Items]
Fair value of loans		0	0
HEI | Multifamily loans, held-for-investment | Variable Interest Entity, Primary Beneficiary | 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 March 31, 2022 and December 31, 2021, assets of consolidated VIEs totaled $10,250,802 and $10,661,081, respectively. At March 31, 2022 and December 31, 2021, liabilities of consolidated VIEs totaled $9,202,156 and $9,619,347, respectively. See Note 4 for further discussion.