Derivative Financial Instruments - Effect of Derivatives (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Derivative Instruments, Gain (Loss) [Line Items]
Net investment income	$ 529	$ 545
Net gains (losses)	43	(16)
Gain (loss) on derivative, net	133	(75)
Not Designated as Hedging Instrument | Credit contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative, net	(1)	(1)
Interest rate contracts | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative, net	126	(56)
Interest rate contracts | Cash Flow Hedging | Designated as Hedging Instrument | Other Comprehensive Income (Loss)
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income	0	0
Interest rate contracts | Cash Flow Hedging | Designated as Hedging Instrument | Investment Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income	0	0
Foreign exchange contracts | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative, net	(2)	1
Foreign exchange contracts | Cash Flow Hedging | Designated as Hedging Instrument | Other Comprehensive Income (Loss)
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income	8	(12)
Foreign exchange contracts | Cash Flow Hedging | Designated as Hedging Instrument | Investment Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income	3	3
Gain (loss) on derivative, net	3	3
Foreign exchange contracts | Cash Flow Hedging | Designated as Hedging Instrument | Gain (Loss) on Investments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative, net	0	0
Foreign exchange contracts | Fair Value Hedging | Investment Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative, net	0	0
Foreign exchange contracts | Fair Value Hedging | Gain (Loss) on Investments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative, net	(2)	2
Foreign exchange contracts | Fair Value Hedging | Designated as Hedging Instrument | Investment Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative, net	0	0
Foreign exchange contracts | Fair Value Hedging | Designated as Hedging Instrument | Gain (Loss) on Investments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative, net	3	(1)
Embedded derivative on reinsurance
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative, net	0	(26)
Embedded derivative on reinsurance | Level 3 | Measured at fair value on a recurring basis
Derivative Instruments, Gain (Loss) [Line Items]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Gain (Loss) Included in Earnings	1	1
Total Realized/Unrealized Gains (Losses) Included in Net income	1	0
Equity contracts | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative, net	10	3
Fixed maturities
Derivative Instruments, Gain (Loss) [Line Items]
Net gains (losses)	(1)	1
Gain (loss) on derivative, net	(1)	1
Managed Custody Guarantees
Derivative Instruments, Gain (Loss) [Line Items]
Net gains (losses)	1	3
Gain (loss) on derivative, net	1	3
Managed custody guarantees | Level 3 | Measured at fair value on a recurring basis
Derivative Instruments, Gain (Loss) [Line Items]
Total Realized/Unrealized Gains (Losses) Included in Net income	$ 2	$ 4