Fair Value Measurement - Quantitative Information - Assets (Details) - Level 3 - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Obligations of state and political subdivisions | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Asset, fair value	$ 6	$ 47
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%	7.40%
Obligations of state and political subdivisions | Maximum | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	22.50%	13.50%
Obligations of state and political subdivisions | Weighted Average | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	7.80%	9.40%
RMBS | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Asset, fair value	$ 154	$ 179
RMBS | Minimum | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	7.50%	7.50%
RMBS | Maximum | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	11.30%	11.30%
RMBS | Weighted Average | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	8.90%	9.00%
CLO contracts | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Asset, fair value	$ 450	$ 428
Others | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Asset, fair value	$ 353	$ 366
Others | Minimum | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	6.20%	7.40%
Others | Maximum | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	11.70%	12.90%
Others | Weighted Average | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	7.80%	11.40%
Financial Guarantee Variable Interest Entities | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Asset, fair value	$ 174	$ 204
Financial Guarantee Variable Interest Entities | Minimum | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	5.50%	6.60%
Financial Guarantee Variable Interest Entities | Maximum | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	10.90%	10.90%
Financial Guarantee Variable Interest Entities | Weighted Average | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	9.40%	7.50%
Consolidated Investment Vehicles | Valuation, Income Approach | Equity securities and warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Asset, fair value	$ 80	$ 297
Yield (as a percent)		10.00%
Consolidated Investment Vehicles | Valuation, Income Approach | Corporate securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)		16.30%
Consolidated Investment Vehicles | Valuation, Income Approach | Structured products
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Asset, fair value	$ 189	$ 46
Consolidated Investment Vehicles | Minimum | Valuation, Income Approach | Structured products
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	14.70%	1280.00%
Consolidated Investment Vehicles | Maximum | Valuation, Income Approach | Structured products
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	21.40%	3710.00%
Consolidated Investment Vehicles | Weighted Average | Valuation, Income Approach | Structured products
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	18.00%	1890.00%
Other | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Asset, fair value	$ 13	$ 47
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)	7.80%	7.70%
Other | Maximum | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	8.40%	8.40%
Other | Weighted Average | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	8.10%	8.10%
Other invested assets | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Asset, fair value	$ 3	$ 5
CPR | RMBS | Minimum | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Conditional prepayment rate (as a percent)	0.10%	3.80%
CPR | RMBS | Maximum | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Conditional prepayment rate (as a percent)	15.00%	16.10%
CPR | RMBS | Weighted Average | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Conditional prepayment rate (as a percent)	3.40%	8.20%
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)	0.20%	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)	21.40%	21.90%
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)	7.80%	12.90%
CDR | RMBS | Minimum | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Conditional prepayment rate (as a percent)	1.50%	1.50%
CDR | RMBS | Maximum | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Conditional prepayment rate (as a percent)	18.80%	12.00%
CDR | RMBS | Weighted Average | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Conditional prepayment rate (as a percent)	5.60%	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%	1.30%
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%	41.00%
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)	10.40%	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)	82.60%	82.50%
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)	82.90%	81.00%
Measurement Input, Discount Rate | Valuation, Income Approach | Corporate securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Asset, fair value		$ 96
Measurement Input, Discount Rate | Minimum | Valuation, Income Approach | Corporate securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)		20.80%
Measurement Input, Discount Rate | Maximum | Valuation, Income Approach | Corporate securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)		23.80%
Measurement Input, Discount Rate | Weighted Average | Valuation, Income Approach | Corporate securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)		21.70%
Measurement Input, Discount Rate | CLO contracts | Minimum | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	1.10%	1.80%
Measurement Input, Discount Rate | CLO contracts | Maximum | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	9.50%	4.10%
Measurement Input, Discount Rate | CLO contracts | Weighted Average | Valuation, Income Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	2.60%	3.00%
Measurement Input, Discount Rate | Consolidated Investment Vehicles | Valuation, Income Approach | Equity securities and warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)	20.90%
Measurement Input, 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%
Measurement Input, 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%
Measurement Input, 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%
Multiple enterprise/revenue value | Valuation, Market Approach | Equity securities and warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Market multiple-price to earnings		1.05
Multiple enterprise/revenue value | Consolidated Investment Vehicles | Valuation, Market Approach | Equity securities and warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Exit multiple-price to book	110.00%	115.00%
Exit multiple-price to earnings	550.00%
Multiple enterprise/revenue value | Consolidated Investment Vehicles | Minimum | Valuation, Market Approach | Equity securities and warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Exit 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-price to earnings		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-price to earnings		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		2.50
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		11.00
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		10.25
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		2.5
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 | 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 | Valuation, Market 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 | Minimum | Valuation, Income Approach | Equity securities and warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Yield (as a percent)		300.00%
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)		400.00%
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)		350.00%
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%
Market multiple-price to earnings	5.50
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%