Derivative Financial Instruments and Hedging Activities - Fair Value (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Derivatives, Fair Value [Line Items]
Fair value of assets (liabilities) available for offset	$ 970	$ 505
Other Assets
Derivatives, Fair Value [Line Items]
Notional	139,523	133,971
Fair Value of Assets	1,560	1,017
Collateral available for netting against liability positions	864	45
Other Liabilities
Derivatives, Fair Value [Line Items]
Fair Value of Liabilities	2,368	691
Collateral held for netting against asset positions	272	376
Derivatives designated as hedges \| Fair value hedges \| Other Assets \| Interest rate swaps \| Level 2
Derivatives, Fair Value [Line Items]
Notional	21,600	15,058
Fair Value of Assets	2	74
Derivatives designated as hedges \| Fair value hedges \| Other Assets \| Foreign currency swaps \| Level 2
Derivatives, Fair Value [Line Items]
Notional	0	682
Fair Value of Assets	0	0
Derivatives designated as hedges \| Fair value hedges \| Other Liabilities \| Interest rate swaps \| Level 2
Derivatives, Fair Value [Line Items]
Fair Value of Liabilities	536	88
Derivatives designated as hedges \| Fair value hedges \| Other Liabilities \| Foreign currency swaps \| Level 2
Derivatives, Fair Value [Line Items]
Fair Value of Liabilities	0	59
Derivatives designated as hedges \| Cash flow hedges \| Other Assets \| Interest rate swaps \| Level 2
Derivatives, Fair Value [Line Items]
Notional	806	611
Fair Value of Assets	25	12
Derivatives designated as hedges \| Cash flow hedges \| Other Assets \| Foreign currency swaps \| Level 2
Derivatives, Fair Value [Line Items]
Notional	7,444	7,419
Fair Value of Assets	7	85
Derivatives designated as hedges \| Cash flow hedges \| Other Liabilities \| Interest rate swaps \| Level 2
Derivatives, Fair Value [Line Items]
Fair Value of Liabilities	0	4
Derivatives designated as hedges \| Cash flow hedges \| Other Liabilities \| Foreign currency swaps \| Level 2
Derivatives, Fair Value [Line Items]
Fair Value of Liabilities	649	201
Derivatives not designated as hedges \| Other Assets \| Interest rate contracts \| Level 2
Derivatives, Fair Value [Line Items]
Notional	109,673	110,053
Fair Value of Assets	1,526	846
Derivatives not designated as hedges \| Other Assets \| Foreign currency contracts \| Level 2
Derivatives, Fair Value [Line Items]
Notional	0	148
Fair Value of Assets	0	0
Derivatives not designated as hedges \| Other Liabilities \| Interest rate contracts \| Level 2
Derivatives, Fair Value [Line Items]
Fair Value of Liabilities	1,183	339
Derivatives not designated as hedges \| Other Liabilities \| Foreign currency contracts \| Level 2
Derivatives, Fair Value [Line Items]
Fair Value of Liabilities	$ 0	$ 0

Derivative Assets (Liabilities), Net, Fair Value, Amount Not Offset Against Collateral

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- Definition

Nominal or face amount used to calculate payments on the derivative asset.

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Fair value, after the 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 not subject to a master netting arrangement and not elected to be offset.

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Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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Fair value, after the 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 not subject to a master netting arrangement and not elected to be offset.

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Amount of right to receive cash collateral under master netting arrangements offset against derivative liabilities.

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- Definition

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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