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Derivative And Credit-Related Financial Instruments (Schedule Of Net Gains Recognized In Income On Customer-Initiated Derivatives) (Details) - Customer-initiated and other activities - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
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Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Net derivative gain recognized in income | $ 26 | $ 29 | $ 53 | $ 51
Interest rate contracts |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Net derivative gain recognized in income | 7 | 10 | 12 | 19
Energy contracts |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Net derivative gain recognized in income | 5 | 6 | 13 | 8
Foreign exchange contracts |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Net derivative gain recognized in income | $ 14 | $ 13 | $ 28 | $ 24

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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4A -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4A + Details
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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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4E -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4E + Details
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