Derivatives (Fair Value Hedges) (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Collateral, Right to Reclaim Cash	$ 75	$ 68
Fixed maturity securities AFS \| Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Hedged Asset, Discontinued Fair Value Hedge, Cumulative Increase (Decrease)	(61)	(67)
Debt Instruments, Carrying Amount	(2,210)	(658)
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	0	0
Mortgages \| Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Debt Instruments, Carrying Amount	(51)	(51)
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	0	0
Future policy benefits [Member] \| Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Debt Instruments, Carrying Amount	(2,473)	(2,509)
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	326	319
Policyholder Account Balances [Member] \| Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Debt Instruments, Carrying Amount	(2,411)	(2,559)
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	$ 136	$ (9)

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Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk, remaining after discontinued hedge. Excludes cumulative basis adjustment related to foreign exchange risk.

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Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk. Excludes cumulative basis adjustment related to foreign exchange risk.

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