Derivative Instruments and Hedging Activities (Fair Value Amounts of Derivative Instruments Reported on our Condensed Consolidated Balance Sheet) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	$ 50	$ 23
Fair value of derivative contracts in payable position	49	42
Derivative, notional amount	44,957	33,833
Credit derivative, maximum exposure, undiscounted	76	82
Designated as hedging instrument
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	47	22
Fair value of derivative contracts in payable position	2	1
Derivative, notional amount	44,703	33,570
Not designated as hedging instrument
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	3	1
Fair value of derivative contracts in payable position	47	41
Derivative, notional amount	254	263
Interest rate contracts \| Not designated as hedging instrument
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	2	0
Fair value of derivative contracts in payable position	0	0
Derivative, notional amount	200	116
Interest rate swaps \| Designated as hedging instrument
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	0	0
Fair value of derivative contracts in payable position	0	0
Derivative, notional amount	39,549	30,619
Interest rate purchased options \| Designated as hedging instrument
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	47	22
Fair value of derivative contracts in payable position	0	0
Derivative, notional amount	5,000	2,800
Interest rate futures and forwards \| Not designated as hedging instrument
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	0	0
Fair value of derivative contracts in payable position	0	0
Derivative, notional amount	77	37
Interest rate written option \| Not designated as hedging instrument
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	2	0
Fair value of derivative contracts in payable position	0
Derivative, notional amount	123	79
Foreign exchange contracts \| Not designated as hedging instrument
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	0	0
Fair value of derivative contracts in payable position	0	1
Derivative, notional amount	52	147
Foreign exchange forwards \| Designated as hedging instrument
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	0	0
Fair value of derivative contracts in payable position	2	1
Derivative, notional amount	154	151
Foreign exchange futures and forwards \| Not designated as hedging instrument
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	0	0
Fair value of derivative contracts in payable position	0	1
Derivative, notional amount	52	147
Other credit derivatives \| Not designated as hedging instrument
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	0	0
Fair value of derivative contracts in payable position	44	39
Equity contracts \| Not designated as hedging instrument
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	1	1
Fair value of derivative contracts in payable position	3	1
Derivative, notional amount	2	0
Equity contract written options \| Not designated as hedging instrument
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	0	0
Fair value of derivative contracts in payable position	3	1
Derivative, notional amount	1	0
Equity contract purchased options \| Not designated as hedging instrument
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	1	1
Fair value of derivative contracts in payable position	0	0
Derivative, notional amount	$ 1	$ 0

Maximum potential amount of future undiscounted payments that could be required under the credit derivative, before reduction for potential recoveries under recourse or collateralization provisions.

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Nominal or face amount used to calculate payment on derivative.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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No definition available.

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