Derivatives - Derivative Balance Sheet Classification (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	$ 11,224	$ 12,129
Fair Value	(42)	(61)
Asset Derivatives	17	33
Liability Derivatives	(59)	(94)
Fixed maturities, available-for-sale
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	413	269
Fair Value	0	0
Asset Derivatives	0	0
Liability Derivatives	0	0
Other investments
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	1,452	9,585
Fair Value	7	23
Asset Derivatives	10	25
Liability Derivatives	(3)	(2)
Other liabilities
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	9,359	2,275
Fair Value	(49)	(84)
Asset Derivatives	7	8
Liability Derivatives	(56)	(92)
Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	2,777	2,626
Fair Value	6	(13)
Asset Derivatives	11	3
Liability Derivatives	(5)	(16)
Designated as Hedging Instrument \| Interest rate swaps
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	2,340	2,340
Fair Value	0	0
Asset Derivatives	0	0
Liability Derivatives	0	0
Designated as Hedging Instrument \| Foreign currency swaps
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	437	286
Fair Value	6	(13)
Asset Derivatives	11	3
Liability Derivatives	(5)	(16)
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	8,447	9,503
Fair Value	(48)	(48)
Asset Derivatives	6	30
Liability Derivatives	(54)	(78)
Not Designated as Hedging Instrument \| Interest rate swaps
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	7,200	7,600
Not Designated as Hedging Instrument \| Interest rate swaps and futures
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	7,567	8,335
Fair Value	(46)	(69)
Asset Derivatives	3	4
Liability Derivatives	(49)	(73)
Not Designated as Hedging Instrument \| Foreign currency swaps and forwards
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	558	269
Fair Value	0	0
Asset Derivatives	0	0
Liability Derivatives	0	0
Not Designated as Hedging Instrument \| Credit derivatives that purchase credit protection
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	112	6
Fair Value	(2)	0
Asset Derivatives	0	0
Liability Derivatives	(2)	0
Not Designated as Hedging Instrument \| Credit derivatives that assume credit risk
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	0	675
Fair Value	0	21
Asset Derivatives	0	21
Liability Derivatives	0	0
Not Designated as Hedging Instrument \| Credit derivatives in offsetting positions
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	210	218
Fair Value	0	0
Asset Derivatives	3	5
Liability Derivatives	$ (3)	$ (5)

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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Nominal or face amount used to calculate payment on derivative.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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