Derivatives - Derivative Balance Sheet Classification (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	$ 11,454	$ 11,224
Fair Value	86	(42)
Asset Derivatives	102	17
Liability Derivatives	(16)	(59)
Available-for-sale Securities [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	539	413
Fair Value	0	0
Asset Derivatives	0	0
Liability Derivatives	0	0
Other investments
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	942	1,452
Fair Value	12	7
Asset Derivatives	12	10
Liability Derivatives	0	(3)
Other liabilities
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	9,973	9,359
Fair Value	74	(49)
Asset Derivatives	90	7
Liability Derivatives	(16)	(56)
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	8,760	8,447
Fair Value	(8)	(48)
Asset Derivatives	7	6
Liability Derivatives	(15)	(54)
Interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	2,155	2,340
Fair Value	1	0
Asset Derivatives	1	0
Liability Derivatives	0	0
Interest rate swaps \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	6,600	7,200
Foreign currency swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	539	437
Fair Value	93	6
Asset Derivatives	94	11
Liability Derivatives	(1)	(5)
Total cash flow hedges
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	2,694	2,777
Fair Value	94	6
Asset Derivatives	95	11
Liability Derivatives	(1)	(5)
Interest rate swaps and futures \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	8,002	7,567
Fair Value	(8)	(46)
Asset Derivatives	3	3
Liability Derivatives	(11)	(49)
Foreign currency swaps and forwards \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	539	558
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	11	112
Fair Value	0	(2)
Asset Derivatives	0	0
Liability Derivatives	0	(2)
Credit derivatives in offsetting positions \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	208	210
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 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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