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Derivatives - Schedule of Gains/(Losses) on Derivatives Associated with Interest Rate Risk Management Activities (Details) - Customer Interest Rate Contracts Hedging - Hedging Instruments And Hedged Items - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Customer interest rate contracts |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gains/(losses) related to interest rate derivatives | $ 195 | $ (744) | $ (268)
Offsetting upstream interest rate contracts |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gains/(losses) related to interest rate derivatives | $ (195) | $ 744 | $ 268

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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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