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Fair Value Measurement - Quantitative Information - Assets (Details) - Level 3 - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021
Obligations of state and political subdivisions | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Asset, fair value | $ 47 | $ 72
Obligations of state and political subdivisions | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 7.40% | 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) | 13.50% | 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) | 9.40% | 6.20%
RMBS | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Asset, fair value | $ 179 | $ 216
RMBS | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 7.50% | 3.80%
RMBS | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 11.30% | 5.60%
RMBS | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 9.00% | 4.50%
Life insurance transactions | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Asset, fair value | $ 342 |
Yield (as a percent) | 11.30% |
CLO contracts | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Asset, fair value | $ 428 | $ 458
Others | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Asset, fair value | $ 24 | $ 38
Others | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 7.40% | 3.20%
Others | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 12.90% | 7.90%
Others | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 12.80% | 7.90%
Financial Guarantee Variable Interest Entities | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Asset, fair value | $ 204 | $ 260
Financial Guarantee Variable Interest Entities | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 6.60% | 1.40%
Financial Guarantee Variable Interest Entities | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 10.90% | 8.00%
Financial Guarantee Variable Interest Entities | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 7.50% | 4.60%
Other | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Asset, fair value | $ 47 | $ 23
Fair value inputs term | 10 years | 10 years
Other | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 7.70% | 2.70%
Other | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 8.40% | 3.30%
Other | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 8.10% | 3.00%
Other invested assets | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Asset, fair value | $ 5 | $ 6
Life insurance transactions | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Asset, fair value |  | $ 367
Yield (as a percent) |  | 5.00%
Consolidated Investment Vehicles | Valuation, Income Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Asset, fair value | $ 297 | $ 239
Yield (as a percent) | 10.00% | 7.70%
Consolidated Investment Vehicles | Valuation, Income Approach | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Asset, fair value | $ 96 |
Yield (as a percent) | 16.30% | 16.40%
Consolidated Investment Vehicles | Valuation, Income Approach | Structured products |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Asset, fair value | $ 46 |
Consolidated Investment Vehicles | Minimum | Valuation, Income Approach | Structured products |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 12.80% |
Consolidated Investment Vehicles | Maximum | Valuation, Income Approach | Structured products |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 37.10% |
Consolidated Investment Vehicles | Weighted Average | Valuation, Income Approach | Structured products |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 18.90% |
CPR | RMBS | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 3.80% | 0.00%
CPR | RMBS | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 16.10% | 22.70%
CPR | RMBS | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 8.20% | 10.40%
CPR | Financial Guarantee Variable Interest Entities | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 0.90% | 0.90%
CPR | Financial Guarantee Variable Interest Entities | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 21.90% | 24.50%
CPR | Financial Guarantee Variable Interest Entities | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 12.90% | 13.30%
CDR | RMBS | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 1.50% | 1.40%
CDR | RMBS | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 12.00% | 12.00%
CDR | RMBS | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 5.90% | 5.90%
CDR | Financial Guarantee Variable Interest Entities | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 1.30% | 1.40%
CDR | Financial Guarantee Variable Interest Entities | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 41.00% | 26.90%
CDR | Financial Guarantee Variable Interest Entities | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 7.60% | 7.60%
Loss severity | RMBS | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 50.00% | 50.00%
Loss severity | RMBS | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 125.00% | 125.00%
Loss severity | RMBS | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 82.50% | 84.90%
Loss severity | Financial Guarantee Variable Interest Entities | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 45.00% | 45.00%
Loss severity | Financial Guarantee Variable Interest Entities | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 100.00% | 100.00%
Loss severity | Financial Guarantee Variable Interest Entities | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Conditional prepayment rate (as a percent) | 81.00% | 81.60%
Discount rate | Valuation, Income Approach | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Asset, fair value |  | $ 91
Discount rate | Minimum | Valuation, Income Approach | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) |  | 14.70%
Discount rate | Maximum | Valuation, Income Approach | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) |  | 21.40%
Discount rate | Weighted Average | Valuation, Income Approach | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) |  | 17.80%
Discount rate | CLO contracts | Minimum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 1.80% | 0.00%
Discount rate | CLO contracts | Maximum | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 4.10% | 2.90%
Discount rate | CLO contracts | Weighted Average | Valuation, Income Approach |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 3.00% | 1.80%
Discount rate | Consolidated Investment Vehicles | Minimum | Valuation, Income Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 19.80% | 14.70%
Discount rate | Consolidated Investment Vehicles | Minimum | Valuation, Income Approach | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 20.80% |
Discount rate | Consolidated Investment Vehicles | Maximum | Valuation, Income Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 25.10% | 23.90%
Discount rate | Consolidated Investment Vehicles | Maximum | Valuation, Income Approach | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 23.80% |
Discount rate | Consolidated Investment Vehicles | Weighted Average | Valuation, Income Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 22.70% | 21.60%
Discount rate | Consolidated Investment Vehicles | Weighted Average | Valuation, Income Approach | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 21.70% |
Multiple enterprise/revenue value | Valuation, Market Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple-enterprise value/revenue |  | 1.10
Multiple enterprise/revenue value | Consolidated Investment Vehicles | Valuation, Market Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple-price to book |  | 185.00%
Multiple enterprise/revenue value | Consolidated Investment Vehicles | Minimum | Valuation, Market Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple-enterprise value/revenue | 1.05 |
Market multiple-price to book | 115.00% |
Market multiple-price to earnings | 450.00% |
Multiple enterprise/revenue value | Consolidated Investment Vehicles | Maximum | Valuation, Market Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple-enterprise value/revenue | 1.10 |
Multiple enterprise/revenue value | Consolidated Investment Vehicles | Weighted Average | Valuation, Market Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple-enterprise value/revenue | 1.08 |
Measurement Input, EBITDA Multiple | Minimum | Valuation, Market Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple - enterprise value/EBITDA |  | 3.00
Measurement Input, EBITDA Multiple | Maximum | Valuation, Market Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple - enterprise value/EBITDA |  | 10.50
Measurement Input, EBITDA Multiple | Weighted Average | Valuation, Market Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple - enterprise value/EBITDA |  | 8.95
Measurement Input, EBITDA Multiple | Consolidated Investment Vehicles | Minimum | Valuation, Market Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple - enterprise value/EBITDA | 2.50 |
Measurement Input, EBITDA Multiple | Consolidated Investment Vehicles | Minimum | Valuation, Market Approach | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple - enterprise value/EBITDA | 2.50 |
Measurement Input, EBITDA Multiple | Consolidated Investment Vehicles | Maximum | Valuation, Market Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple - enterprise value/EBITDA | 11.00 |
Measurement Input, EBITDA Multiple | Consolidated Investment Vehicles | Maximum | Valuation, Market Approach | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple - enterprise value/EBITDA | 2.75 |
Measurement Input, EBITDA Multiple | Consolidated Investment Vehicles | Weighted Average | Valuation, Market Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple - enterprise value/EBITDA | 10.25 |
Measurement Input, EBITDA Multiple | Consolidated Investment Vehicles | Weighted Average | Valuation, Market Approach | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Market multiple - enterprise value/EBITDA | 2.63 |
Measurement Input, Long-Term Revenue Growth Rate | Consolidated Investment Vehicles | Minimum | Valuation, Income Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 3.00% |
Measurement Input, Long-Term Revenue Growth Rate | Consolidated Investment Vehicles | Maximum | Valuation, Income Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 4.00% |
Measurement Input, Long-Term Revenue Growth Rate | Consolidated Investment Vehicles | Weighted Average | Valuation, Income Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 3.50% |
Measurement Input, Exit Multiple, EBITDA | Consolidated Investment Vehicles | Valuation, Market Approach | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 800.00% |
Measurement Input, Exit Multiple, EBITDA | Consolidated Investment Vehicles | Minimum | Valuation, Market Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 800.00% |
Measurement Input, Exit Multiple, EBITDA | Consolidated Investment Vehicles | Maximum | Valuation, Market Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 1200.00% |
Measurement Input, Exit Multiple, EBITDA | Consolidated Investment Vehicles | Weighted Average | Valuation, Market Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 1053.00% |
Measurement Input, Price to Book | Consolidated Investment Vehicles | Valuation, Market Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 130.00% |
Measurement Input, Price to Earnings | Consolidated Investment Vehicles | Valuation, Market Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 550.00% |
Measurement Input, Cost to Sell | Consolidated Investment Vehicles | Valuation, Income Approach | Equity securities and warrants |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 100.00% |
Measurement Input, Cost to Sell | Consolidated Investment Vehicles | Valuation, Income Approach | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 100.00% |

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