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v3.20.4

Other Investments - Additional Information (Details) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2019 partnership | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) partnership
Investment [Line Items] |  |  |  |
Number of partnerships consolidated | partnership | 2 |  |  | 2
Commitment to fund partnership |  | $ 94,000,000 |  |
Equity investment income |  | 1,037,000 | $ 1,405,000 | $ 618,000
Investment fair value changes, net |  | (588,438,000) | 35,500,000 | (25,689,000)
Interest income |  | 571,916,000 | 622,281,000 | $ 378,717,000
Light-Renovation Multifamily Loans |  |  |  |
Investment [Line Items] |  |  |  |
Equity investment income |  | 1,000,000 | 1,000,000 |
Carrying amount of equity method investments |  | 0 |  |
Commitment to fund partnership, funded amount |  | 0 |  |
Payments to Acquire Retained Interest in Securitized Receivables |  | 56,000,000 |  |
MSRs |  |  |  |
Investment [Line Items] |  |  |  |
Servicing asset, fair value |  | 8,815,000 | 42,224,000 |
Servicing assets |  | 2,590,000,000 | 4,350,000,000 |
Mortgage Servicing Rights Income Including Market Valuation Changes of MSRs |  | (10,000,000) | 4,000,000 |
Shared home appreciation options |  |  |  |
Investment [Line Items] |  |  |  |
Payments to acquire investments |  | 47,000,000 |  |
Commitment To Fund Investment | Shared home appreciation options |  |  |  |
Investment [Line Items] |  |  |  |
Investment fair value changes, net |  | (2,000,000) | 1,000,000 |
Residential Loans |  |  |  |
Investment [Line Items] |  |  |  |
Servicing asset, fair value |  | 231,489,000 | 169,204,000 |
Servicing asset, unpaid principal balance on underlying loan |  | 9,140,000,000 |  |
Excess MSRs |  |  |  |
Investment [Line Items] |  |  |  |
Servicing asset, fair value |  | 34,418,000 | 31,814,000 |
Investment fair value changes, net |  | (8,000,000) | (3,000,000) |
Interest income |  | 12,000,000 | 8,000,000 |
Servicer advance financing |  |  |  |
Investment [Line Items] |  |  |  |
Collateral amounts |  | 218,000,000 |  |
Equity investment income |  | 11,000,000 | 11,000,000 |
Investment fair value changes, net |  | $ (9,000,000) | $ 3,000,000 |

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