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Other Investments - Additional Information (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2021 USD ($)	Dec. 31, 2021 USD ($) investment	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($) partnership	Dec. 31, 2018 partnership
Investment [Line Items]
Number of partnerships consolidated \| partnership				2	2
Commitment to fund partnership		$ 148,000
Collateral amounts		1,306,932	$ 1,084,929
Investment fair value changes, net		128,049	(588,438)	$ 35,500
Interest income		574,926	571,916	622,281
Other income, net		12,018	4,188	19,257
Variable Interest Entity, Primary Beneficiary
Investment [Line Items]
Investment fair value changes, net		90,121	(167,856)
Estimated fair value of investments		1,033,913	789,228
Interest income		400,292	391,191
Variable Interest Entity, Primary Beneficiary \| Collateralized Financing Entities \| Point
Investment [Line Items]
Estimated fair value of investments	$ 10,000
MSRs
Investment [Line Items]
Servicing asset, fair value		12,438	8,815
Servicing assets		2,120,000	2,590,000
MSR income (loss)		2,000	(10,000)	4,000
HEIs
Investment [Line Items]
Investments acquired		78,000
Transfer to investments	172,000
HEIs \| Redwood
Investment [Line Items]
Servicing asset, fair value		33,000
HEIs \| Point HEI
Investment [Line Items]
Servicing asset, fair value		160,000
Strategic Investments
Investment [Line Items]
Other income, net		$ 800
Strategic Investments \| RWT Horizons
Investment [Line Items]
Number of investments made \| investment		15
Investments		$ 21,000
Strategic Investments \| Churchill Finance
Investment [Line Items]
Number of investments made \| investment		1
Commitment To Fund Investment \| Shared home appreciation options
Investment [Line Items]
Investment fair value changes, net		$ 13,000	(2,000)
Residential Loans
Investment [Line Items]
Servicing asset, fair value		350,923	231,489
Servicing asset, unpaid principal balance on underlying loan		13,630,000
Excess MSRs
Investment [Line Items]
Servicing asset, fair value		44,231	34,418
Investment fair value changes, net		(8,000)	(8,000)	(3,000)
Fair value option elected aggregate carrying amount, asset		18,000	11,000
Interest income		13,000	12,000	8,000
HEIs
Investment [Line Items]
Fair value option elected aggregate carrying amount, asset	122,000
Other investments held by noncontrolling interests	17,000
Point HEI
Investment [Line Items]
Investment fair value changes, net		200
Other investments, interest expense		1,400
Point HEI \| Variable Interest Entity, Primary Beneficiary
Investment [Line Items]
Amortized cost	$ 146,000
Servicer advance financing
Investment [Line Items]
Collateral amounts		311,000
Income (loss) on investments		12,000	11,000	11,000
Investment fair value changes, net		$ (1,000)	$ (9,000)	$ 3,000