Other Investments - Additional Information (Details) $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($) partnership	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
Net Investment Income [Line Items]
Number of partnerships consolidated \| partnership	2
Commitment to fund partnership	$ 94,000
Servicing asset, fair value	192,852		$ 217,656
Collateral amounts	1,139,638		1,084,929
Equity investment income	0	$ 848
Investment fair value changes, net	45,087	(870,832)
Interest income	128,305	198,081
Servicer advance financing
Net Investment Income [Line Items]
Collateral amounts	193,000
Equity investment income	3,000	3,000
Investment fair value changes, net	(200)	(6,000)
Held-for-sale residential loans
Net Investment Income [Line Items]
Servicing asset, fair value	206,525		231,489
Servicing asset, unpaid principal balance on underlying loan	8,600,000
Excess MSRs
Net Investment Income [Line Items]
Servicing asset, fair value	32,465		34,418
Investment fair value changes, net	(2,000)	(9,000)
Interest income	3,000	3,000
Shared home appreciation options
Net Investment Income [Line Items]
Payments to acquire investments	47,000
Shared home appreciation options \| Commitment To Fund Investment
Net Investment Income [Line Items]
Investment fair value changes, net	5,000	(8,000)
MSRs
Net Investment Income [Line Items]
Servicing asset, fair value	7,945		8,815
Aggregate principal balance	2,070,000		$ 2,590,000
MSR income (losses), net	$ 1,000	$ (2,000)

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Number Of Partnerships Consolidated

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Servicing Asset At Fair Value, Unpaid Principal Balance On Underlying Loans

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Amount of assets pledged to secure a debt instrument.

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