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Significant Group Concentrations of Credit Risk Significant Group Concentrations of Credit Risk (Schedule of Automotive Industry Outstanding Loans and Total Exposure) (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Concentration Risk [Line Items] |  |
Total automotive loans | $ 6,277 | $ 7,039
Total automotive exposure | $ 10,336 | 12,162
Concentration Risk Threshold - Auto | 12.00% |
Automotive Production |  |
Concentration Risk [Line Items] |  |
Total automotive loans | $ 764 | 848
Total automotive exposure | 1,661 | 1,744
Automotive Dealer |  |
Concentration Risk [Line Items] |  |
Total automotive loans | 5,513 | 6,191
Total automotive exposure | $ 8,675 | $ 10,418

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- Definition Total automotive exposure including loans and other credit commitments to automotive dealers and to borrowers involved with automotive production. + References No definition available. + Details
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