Derivative Instruments and Hedging Activities (Fair Value Amounts of Derivative Instruments Reported on our Condensed Consolidated Balance Sheet) (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	$ 4	$ 7
Fair value of derivative contracts in payable position	55	62
Derivative, notional amount	25,528	18,169
Credit derivative, maximum exposure, undiscounted	102	119
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	1	2
Derivative, notional amount	24,931	17,210
Not designated as hedging instrument
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	4	7
Fair value of derivative contracts in payable position	54	60
Derivative, notional amount	597	959
Interest rate contracts \| Not designated as hedging instrument
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	3	6
Fair value of derivative contracts in payable position	4	2
Derivative, notional amount	441	803
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	24,780	17,039
Interest rate futures and forwards \| 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	168	223
Interest rate written options \| Not designated as hedging instrument
Derivatives, Fair Value [Line Items]
Fair value of derivative contracts in receivable position	2	5
Fair value of derivative contracts in payable position	4	2
Derivative, notional amount	273	580
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	2	1
Derivative, notional amount	156	154
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	1	2
Derivative, notional amount	151	171
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	2	1
Derivative, notional amount	156	154
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	48	56
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	0	1
Derivative, notional amount	0	2
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	0	1
Derivative, notional amount	0	2
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	$ 0	$ 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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 4K
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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No definition available.

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