Derivatives - Derivative Balance Sheet Classification (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	$ 12,923	$ 10,755
Fair Value	19	47
Asset Derivatives	60	62
Liability Derivatives	(41)	(15)
Available-for-sale Securities [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	568	569
Fair Value	0	0
Asset Derivatives	0	0
Liability Derivatives	0	0
Other investments
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	9,338	9,108
Fair Value	50	34
Asset Derivatives	58	38
Liability Derivatives	(8)	(4)
Other liabilities
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	3,017	1,078
Fair Value	(31)	13
Asset Derivatives	2	24
Liability Derivatives	(33)	(11)
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	9,750	8,032
Fair Value	(29)	(6)
Asset Derivatives	6	5
Liability Derivatives	(35)	(11)
Interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	2,605	2,155
Fair Value	0	0
Asset Derivatives	1	0
Liability Derivatives	(1)	0
Interest rate swaps \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	6,600	6,600
Foreign currency swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	568	568
Fair Value	48	53
Asset Derivatives	53	57
Liability Derivatives	(5)	(4)
Total cash flow hedges
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	3,173	2,723
Fair Value	48	53
Asset Derivatives	54	57
Liability Derivatives	(6)	(4)
Interest rate swaps and futures \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	6,964	7,245
Fair Value	(6)	(6)
Asset Derivatives	2	2
Liability Derivatives	(8)	(8)
Foreign currency swaps and forwards \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	568	569
Fair Value	0	0
Asset Derivatives	0	0
Liability Derivatives	0	0
Credit derivatives that purchase credit protection \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	2,011	11
Fair Value	(23)	0
Asset Derivatives	0	0
Liability Derivatives	(23)	0
Credit derivatives in offsetting positions \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	207	207
Fair Value	0	0
Asset Derivatives	4	3
Liability Derivatives	$ (4)	$ (3)

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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