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v3.20.4

Principles of Consolidation - Additional Information (Details) $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2020 | Mar. 31, 2020 USD ($) | Sep. 30, 2019 partnership | Dec. 31, 2018 partnership | Dec. 31, 2020 USD ($) entity
Variable Interest Entity [Line Items] |  |  |  |  |
Deconsolidation, realized market valuation gain (loss) |  | $ (72) |  |  |
Number of partnerships consolidated | partnership |  |  | 2 | 2 |
VIE, ownership interest rate | 80.00% |  |  |  |
Variable Interest Entity, Primary Beneficiary |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Number of securitization entities to which asset transferred | entity |  |  |  |  | 5
Variable Interest Entity, Not Primary Beneficiary |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Number of securitization entities to which asset transferred | entity |  |  |  |  | 53
Legacy Sequoia | Variable Interest Entity, Primary Beneficiary |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Estimated fair value of investments |  |  |  |  | $ 5
Sequoia Choice | Variable Interest Entity, Primary Beneficiary |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Estimated fair value of investments |  |  |  |  | 220
Freddie Mac SLST | Variable Interest Entity, Primary Beneficiary |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Estimated fair value of investments |  |  |  |  | 430
Amortized cost |  |  |  |  | 210
Freddie Mac K-Series | Variable Interest Entity, Primary Beneficiary |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Estimated fair value of investments |  |  |  |  | 28
CAFL | Variable Interest Entity, Primary Beneficiary |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Estimated fair value of investments |  |  |  |  | 242
Servicing Investment | Variable Interest Entity, Primary Beneficiary |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
MSRs |  |  |  |  | $ 68

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