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Fair Value Measurement - Quantitative Information - Assets (Details) - Level 3 $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
Credit derivative liabilities, net |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Internal floor (as a percent) | 880.00% | 880.00%
Valuation, Income Approach | Credit derivative liabilities, net |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair value | $ (156) | $ (154)
Valuation, Income Approach | Warehouse financing debt |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair value | (31) | (23)
Valuation, Income Approach | Securitized borrowing |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair value | $ (21) | $ (17)
Minimum | Credit derivative liabilities, net |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Hedge cost (as a percent) | 1190.00% | 800.00%
Bank profit (as a percent) | 0.00% | 0.00%
Minimum | Valuation, Income Approach | Warehouse financing debt |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 16.20% | 12.60%
Maximum | Credit derivative liabilities, net |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Hedge cost (as a percent) | 5320.00% | 3710.00%
Bank profit (as a percent) | 21130.00% | 18780.00%
Maximum | Valuation, Income Approach | Warehouse financing debt |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 27.70% | 16.00%
Weighted Average | Credit derivative liabilities, net |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Hedge cost (as a percent) | 2180.00% | 1260.00%
Bank profit (as a percent) | 7220.00% | 6790.00%
Weighted Average | Valuation, Income Approach | Warehouse financing debt |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 23.70% | 13.80%
Discount margin | Valuation, Income Approach | Securitized borrowing |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 24.20% | 23.90%
Obligations of state and political subdivisions | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Total assets carried at fair value | $ 70 | $ 72
Obligations of state and political subdivisions | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 2.60% | 4.40%
Obligations of state and political subdivisions | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 27.10% | 24.50%
Obligations of state and political subdivisions | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 6.70% | 6.20%
RMBS | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Total assets carried at fair value | $ 200 | $ 216
RMBS | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 4.80% | 3.80%
RMBS | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 6.40% | 5.60%
RMBS | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 5.60% | 4.50%
RMBS | CPR | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 0.00% | 0.00%
RMBS | CPR | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 22.50% | 22.70%
RMBS | CPR | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 11.00% | 10.40%
RMBS | CDR | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 1.60% | 1.40%
RMBS | CDR | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 12.00% | 12.00%
RMBS | CDR | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 5.80% | 5.90%
RMBS | Loss severity | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 50.00% | 50.00%
RMBS | Loss severity | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 125.00% | 125.00%
RMBS | Loss severity | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 85.00% | 84.90%
Life insurance transactions | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Total assets carried at fair value | $ 370 | $ 367
Yield (as a percent) | 6.00% | 5.00%
CLOs | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Total assets carried at fair value | $ 437 | $ 458
CLOs | Discount margin | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 1.00% | 0.00%
CLOs | Discount margin | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 3.10% | 2.90%
CLOs | Discount margin | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 2.10% | 1.80%
Others | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Total assets carried at fair value | $ 35 | $ 38
Others | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 5.00% | 3.20%
Others | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 10.30% | 7.90%
Others | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 10.20% | 7.90%
FG VIEs and other | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Total assets carried at fair value | $ 267 | $ 260
FG VIEs and other | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 1.70% | 1.40%
FG VIEs and other | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 8.60% | 8.00%
FG VIEs and other | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 5.40% | 4.60%
FG VIEs and other | CPR | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 0.90% | 0.90%
FG VIEs and other | CPR | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 25.50% | 24.50%
FG VIEs and other | CPR | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 13.20% | 13.30%
FG VIEs and other | CDR | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 1.00% | 1.40%
FG VIEs and other | CDR | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 26.90% | 26.90%
FG VIEs and other | CDR | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 7.20% | 7.60%
FG VIEs and other | Loss severity | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 45.00% | 45.00%
FG VIEs and other | Loss severity | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 100.00% | 100.00%
FG VIEs and other | Loss severity | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 77.10% | 81.60%
Equity Securities and Warrants | Assets of Consolidated Investment Vehicles | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Total assets carried at fair value | $ 243 | $ 239
Yield (as a percent) | 8.00% | 7.70%
Equity Securities and Warrants | Discount margin | Assets of Consolidated Investment Vehicles | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 13.00% | 14.70%
Equity Securities and Warrants | Discount margin | Assets of Consolidated Investment Vehicles | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 24.20% | 23.90%
Equity Securities and Warrants | Discount margin | Assets of Consolidated Investment Vehicles | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 21.80% | 21.60%
Equity Securities and Warrants | Exit cap rate | Assets of Consolidated Investment Vehicles | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 12.00% |
Equity Securities and Warrants | Terminal growth rate | Assets of Consolidated Investment Vehicles | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 4.00% |
Equity Securities and Warrants | Measurement Input, Revenue Multiple | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate | 185.00% | 185.00%
Equity Securities and Warrants | Measurement Input, Revenue Multiple | Valuation, Market Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple-enterprise value/revenue | 1.10000 |
Equity Securities and Warrants | Measurement Input, Revenue Multiple | Valuation, Exit Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Exit multiple, price to book (as a percent) | 130.00% |
Exit multiple (as a percent) | 1100.00% |
Equity Securities and Warrants | Measurement Input, EBITDA Multiple | Minimum | Valuation, Market Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple-enterprise value/EBITDA | 3.00000 |
Equity Securities and Warrants | Measurement Input, EBITDA Multiple | Minimum | Valuation, Exit Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Exit multiple, EBITDA | 800.00% |
Equity Securities and Warrants | Measurement Input, EBITDA Multiple | Maximum | Valuation, Market Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple-enterprise value/EBITDA | 10.50 |
Equity Securities and Warrants | Measurement Input, EBITDA Multiple | Maximum | Valuation, Exit Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Exit multiple, EBITDA | 1200.00% |
Equity Securities and Warrants | Measurement Input, EBITDA Multiple | Weighted Average | Valuation, Market Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple-enterprise value/EBITDA | 9.21000 |
Equity Securities and Warrants | Measurement Input, EBITDA Multiple | Weighted Average | Valuation, Exit Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Exit multiple, EBITDA | 1043.00% |
Equity Securities and Warrants | Cost | Assets of Consolidated Investment Vehicles | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 100.00% |
Other | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Total assets carried at fair value | $ 25 | $ 23
Term (years) | 10 years | 10 years
Other | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 3.10% | 2.70%
Other | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 3.70% | 3.30%
Other | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 3.40% | 3.00%
Corporate securities | Assets of Consolidated Investment Vehicles | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 17.20% | 16.40%
Corporate securities | Discount margin | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Total assets carried at fair value | $ 83 | $ 91
Corporate securities | Discount margin | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 21.40% | 14.70%
Corporate securities | Discount margin | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 23.70% | 21.40%
Corporate securities | Discount margin | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 22.30% | 17.80%
Corporate securities | Measurement Input, EBITDA Multiple | Valuation, Market Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple-enterprise value/EBITDA | 3.00000 |
Corporate securities | Measurement Input, EBITDA Multiple | Valuation, Exit Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Exit multiple, EBITDA | 800.00% |
Corporate securities | Cost | Assets of Consolidated Investment Vehicles | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 100.00% |
Assets of Consolidated Investment Vehicles | Measurement Input, Revenue Multiple | Valuation, Market Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple-enterprise value/revenue |  | 1.10000
Assets of Consolidated Investment Vehicles | Measurement Input, EBITDA Multiple | Minimum | Valuation, Market Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple-enterprise value/EBITDA |  | 3.00000
Assets of Consolidated Investment Vehicles | Measurement Input, EBITDA Multiple | Maximum | Valuation, Market Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple-enterprise value/EBITDA |  | 10.50
Assets of Consolidated Investment Vehicles | Measurement Input, EBITDA Multiple | Weighted Average | Valuation, Market Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple-enterprise value/EBITDA |  | 8.95000

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