Residential Investor Loans - Schedule of Characteristics of Residential Investor Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Term at Redwood \| HEI at Redwood
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
UPB	$ 177,618	$ 152,213
Average UPB of loans	1,759	4,006
Fair value of loans	$ 158,637	$ 144,359
Weighted average coupon rate (as a percent)	6.84%	6.92%
Weighted average remaining loan term (years)	9 years	7 years
Market value of loans pledged as collateral under debt facilities	$ 120,417	$ 124,934
Unpaid principal balance of loans with 90+ day delinquencies/Unpaid principal balance of loans in foreclosure	27,529	28,263
Average UPB of 90+ days delinquent loans/Average UPB of loans in foreclosure	27,529	14,132
Fair value of loans in foreclosure	8,500	16,822
Term at Redwood \| HEI at Redwood \| Financing Receivables, Equal to Greater than 90 Days Past Due
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Fair value of loans	12,366	16,822
Unpaid principal balance of loans with 90+ day delinquencies/Unpaid principal balance of loans in foreclosure	33,065	28,263
Average UPB of 90+ days delinquent loans/Average UPB of loans in foreclosure	8,266	14,132
Term at CAFL \| CAFL Securitization Entities
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
UPB	2,639,485	3,194,131
Average UPB of loans	3,084	3,028
Fair value of loans	$ 2,485,069	$ 2,971,725
Weighted average coupon rate (as a percent)	5.35%	5.34%
Weighted average remaining loan term (years)	4 years	5 years
Unpaid principal balance of loans with 90+ day delinquencies/Unpaid principal balance of loans in foreclosure	$ 24,648	$ 15,708
Average UPB of 90+ days delinquent loans/Average UPB of loans in foreclosure	2,465	2,244
Term at CAFL \| CAFL Securitization Entities \| Financing Receivables, Equal to Greater than 90 Days Past Due
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Unpaid principal balance of loans with 90+ day delinquencies/Unpaid principal balance of loans in foreclosure	194,143	143,623
Average UPB of 90+ days delinquent loans/Average UPB of loans in foreclosure	3,734	3,192
Business Purpose Bridge Loans \| HEI at Redwood
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
UPB	1,166,213	1,360,957
Average UPB of loans	5,350	8,453
Fair value of loans	$ 1,120,281	$ 1,341,618
Weighted average coupon rate (as a percent)	9.11%	10.41%
Weighted average remaining loan term (years)	1 year	1 year
Market value of loans pledged as collateral under debt facilities	$ 1,070,327	$ 1,298,198
Unpaid principal balance of loans with 90+ day delinquencies/Unpaid principal balance of loans in foreclosure	86,260	79,841
Average UPB of 90+ days delinquent loans/Average UPB of loans in foreclosure	6,635	5,323
Fair value of loans in foreclosure	67,858	69,046
Business Purpose Bridge Loans \| HEI at Redwood \| Financing Receivables, Equal to Greater than 90 Days Past Due
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Fair value of loans	102,321	86,137
Unpaid principal balance of loans with 90+ day delinquencies/Unpaid principal balance of loans in foreclosure	129,229	96,934
Average UPB of 90+ days delinquent loans/Average UPB of loans in foreclosure	8,077	5,702
Business Purpose Bridge Loans \| CAFL Securitization Entities
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
UPB	810,285	756,574
Average UPB of loans	1,605	2,162
Fair value of loans	$ 823,103	$ 762,596
Weighted average coupon rate (as a percent)	9.76%	10.82%
Weighted average remaining loan term (years)	1 year	1 year
Unpaid principal balance of loans with 90+ day delinquencies/Unpaid principal balance of loans in foreclosure	$ 3,663	$ 3,931
Average UPB of 90+ days delinquent loans/Average UPB of loans in foreclosure	916	1,310
Fair value of loans in foreclosure	3,715
Business Purpose Bridge Loans \| CAFL Securitization Entities \| Financing Receivables, Equal to Greater than 90 Days Past Due
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Unpaid principal balance of loans with 90+ day delinquencies/Unpaid principal balance of loans in foreclosure	20,964	10,646
Average UPB of 90+ days delinquent loans/Average UPB of loans in foreclosure	$ 1,233	$ 1,774

Fair Value, Option, Loans Held As Assets, 90 Days Or More Past Due, Average

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Fair Value, Option, Loans Held As Assets, Aggregate Amount In Foreclosure

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Financing Receivable, Contract Maturities

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Financing Receivables, Weighted Average Interest Rate

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Loan, Managed and Securitized or Asset-Backed Financing Arrangement, Principal Outstanding, Average

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 29
-Publisher SEC

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This item represents the aggregate fair value of loans held as assets that are 90 days or more past due for which the fair value option has been elected.

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- Definition

Amount of realized and unrealized gain (loss) on investment.

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-SubTopic 10
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Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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-Topic 310
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- Definition

This is the sum of principal amount outstanding for both securitized and unsecuritized loans of all types.

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