Derivatives - Derivative Balance Sheet Classification (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	$ 10,973	$ 11,224
Fair Value	(14)	(42)
Asset Derivatives	30	17
Liability Derivatives	(44)	(59)
Available-for-sale Securities [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	452	413
Fair Value	0	0
Asset Derivatives	0	0
Liability Derivatives	0	0
Other investments
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	9,067	1,452
Fair Value	8	7
Asset Derivatives	17	10
Liability Derivatives	(9)	(3)
Other liabilities
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	1,454	9,359
Fair Value	(22)	(49)
Asset Derivatives	13	7
Liability Derivatives	(35)	(56)
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	8,326	8,447
Fair Value	(28)	(48)
Asset Derivatives	12	6
Liability Derivatives	(40)	(54)
Interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	2,155	2,340
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	7,200	7,200
Foreign currency swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	492	437
Fair Value	14	6
Asset Derivatives	17	11
Liability Derivatives	(3)	(5)
Total cash flow hedges
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	2,647	2,777
Fair Value	14	6
Asset Derivatives	18	11
Liability Derivatives	(4)	(5)
Interest rate swaps and futures \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	7,275	7,567
Fair Value	(29)	(46)
Asset Derivatives	4	3
Liability Derivatives	(33)	(49)
Foreign currency swaps and forwards \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	593	558
Fair Value	1	0
Asset Derivatives	1	0
Liability Derivatives	0	0
Credit derivatives that purchase credit protection \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	7	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	210	210
Fair Value	0	0
Asset Derivatives	3	3
Liability Derivatives	(3)	(3)
Commodity Option \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	241	0
Fair Value	0	0
Asset Derivatives	4	0
Liability Derivatives	$ (4)	$ 0

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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- Definition

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

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- Definition

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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