Derivative Financial Instruments - Net Realized Gains (Losses) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Derivatives, Fair Value [Line Items]
Net Investment Income	$ 413,000,000	$ 376,000,000
Derivative, Gain (Loss) on Derivative, Net	(18,000,000)	90,000,000
Realized capital gains (losses)	(19,000,000)	15,000,000
Interest rate contracts | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Gain (Loss) on Derivative, Net	(38,000,000)	89,000,000
Interest rate contracts | Cash flow hedges | Designated as Hedging Instrument | Other Comprehensive Income (Loss)
Derivatives, Fair Value [Line Items]
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred	0	0
Interest rate contracts | Cash flow hedges | Designated as Hedging Instrument | Investment Income
Derivatives, Fair Value [Line Items]
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred	0	0
Foreign exchange contracts | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Gain (Loss) on Derivative, Net	1,000,000	1,000,000
Foreign exchange contracts | Cash flow hedges | Designated as Hedging Instrument | Other Comprehensive Income (Loss)
Derivatives, Fair Value [Line Items]
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred	(13,000,000)	7,000,000
Foreign exchange contracts | Cash flow hedges | Designated as Hedging Instrument | Investment Income
Derivatives, Fair Value [Line Items]
Derivative, Gain (Loss) on Derivative, Net	1,000,000	2,000,000
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred	1,000,000	2,000,000
Foreign exchange contracts | Cash flow hedges | Designated as Hedging Instrument | Gain (Loss) on Investments
Derivatives, Fair Value [Line Items]
Derivative, Gain (Loss) on Derivative, Net	0	0
Fixed maturities
Derivatives, Fair Value [Line Items]
Derivative, Gain (Loss) on Derivative, Net	4,000,000	(1,000,000)
Realized capital gains (losses)	4,000,000	(1,000,000)
Managed Custody Guarantees
Derivatives, Fair Value [Line Items]
Derivative, Gain (Loss) on Derivative, Net	(1,000,000)	1,000,000
Realized capital gains (losses)	(1,000,000)	1,000,000
Stabilizer
Derivatives, Fair Value [Line Items]
Derivative, Gain (Loss) on Derivative, Net	4,000,000	0
Realized capital gains (losses)	4,000,000	0
Reinsurance agreements
Derivatives, Fair Value [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ 12,000,000	$ 0