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Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

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Other Investments - Additional Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022 USD ($) investment partnership	Sep. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)
Net Investment Income [Line Items]
Number of partnerships consolidated \| partnership	2
Commitment to fund partnership	$ 148,000
Servicing asset, fair value	265,949			$ 310,953
Collateral amounts	1,683,830			1,306,932
Investment fair value changes, net	(6,120)		$ 45,087
Other income, net	5,983		3,843
Interest income	$ 189,400		128,305
Variable Interest Entity, Primary Beneficiary
Net Investment Income [Line Items]
Number of partnerships consolidated \| partnership	2
Investment fair value changes, net	$ 1,371		15,705
Interest income	140,316		94,871
Variable Interest Entity, Primary Beneficiary \| HEI
Net Investment Income [Line Items]
Investment fair value changes, net	3,411		0
Interest income	0		0
Variable Interest Entity, Primary Beneficiary \| Collateralized Financing Entities
Net Investment Income [Line Items]
Value of our investments in VIEs(1)	1,040,987			1,033,913
Variable Interest Entity, Primary Beneficiary \| Collateralized Financing Entities \| HEI
Net Investment Income [Line Items]
Value of our investments in VIEs(1)	13,753			10,451
Servicer advance financing
Net Investment Income [Line Items]
Collateral amounts	266,000
Equity investment income	5,000
Investment fair value changes, net	(3,000)		(200)
Servicer advance financing \| Other Interest Income
Net Investment Income [Line Items]
Investment fair value changes, net			3,000
Held-for-sale residential loans
Net Investment Income [Line Items]
Servicing asset, fair value	302,837			350,923
Servicing asset, unpaid principal balance on underlying loan	12,700,000
Excess MSRs
Net Investment Income [Line Items]
Servicing asset, fair value	43,023			44,231
Investment fair value changes, net	(1,000)		(2,000)
Fair value option elected aggregate carrying amount, asset	5,000
Interest income	4,000		3,000
Point HEI
Net Investment Income [Line Items]
Investment fair value changes, net	3,000
Other Investments, Interest Expense	1,000
MSRs
Net Investment Income [Line Items]
Servicing asset, fair value	19,739			12,438
Aggregate principal balance	2,360,000			$ 2,120,000
MSR income (losses), net	4,300		1,000
Shared home appreciation options \| Redwood
Net Investment Income [Line Items]
Servicing asset, fair value	74,000
Shared home appreciation options \| Point HEI
Net Investment Income [Line Items]
Servicing asset, fair value	153,000
Shared home appreciation options \| Commitment To Fund Investment
Net Investment Income [Line Items]
Investment fair value changes, net	1,000		$ 5,000
HEIs
Net Investment Income [Line Items]
Payments to acquire other investments	125,000	$ 125,000
Other commitments made	250,000
Investments	70,000
Payments to acquire investments	117,000
Strategic Investments
Net Investment Income [Line Items]
Other income, net	$ 100
Strategic Investments \| RWT Horizons
Net Investment Income [Line Items]
Number of investments made \| investment	21
Investments	$ 25,000
Strategic Investments \| Churchill Finance
Net Investment Income [Line Items]
Number of investments made \| investment	2