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Credit Quality And Allowance For Credit Losses (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | Dec. 31, 2023
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Loan interest receivable |  | $ 277 |  | $ 277 |  | $ 313
Interest income |  | 2 | $ 2 | 8 | $ 8 |
Commitments to lend additional funds to TDR borrowers |  | $ 0 |  | $ 0 |  | $ 0
Weighted-Average Term Extension (in months) |  | 1 year 5 months 23 days | 9 months 7 days | 1 year 3 months 11 days | 11 months 1 day |
Subsequent default during period |  |  |  | $ 7 |  |
Real Estate Acquired Through Foreclosure |  | $ 4 |  | $ 4 |  |
Business loans: |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  | 1 year 29 days | 7 months 13 days | 1 year 18 days | 9 months 22 days |
Retail loans: | Residential mortgage |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  | 7 years 11 months 5 days |  | 1 year 18 days |  |
Commercial | Other business lines | Commercial mortgage: |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) | [1] |  |  |  | 1 year 9 months 29 days |
Commercial | Business loans: |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  | 1 year 22 days | 7 months 13 days | 1 year 22 days | 8 months 1 day |
Commercial | Business loans: | International |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  | 10 months 21 days |  | 11 months 12 days |  |
Commercial | Business loans: | Commercial mortgage: |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  | 1 year 4 months 28 days | 8 months 23 days | 1 year 11 days | 1 year 9 months 29 days |
Commercial | Business loans: | Real estate construction |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  |  | 6 months |  | 6 months |
Commercial | Business loans: | Other business lines | Commercial mortgage: |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) | [1] | 1 year 4 months 28 days | 8 months 23 days | 1 year 11 days |  |
Commercial | Business loans: | Other business lines | Real estate construction |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  |  | 6 months |  | 6 months |
Consumer | Retail loans: |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  | 8 years 3 months 29 days | 10 years 11 months 5 days | 8 years 7 months 6 days | 10 years 9 months |
Consumer | Retail loans: | Home equity |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  | 10 years | 10 years 11 months 5 days | 9 years 11 months 9 days | 10 years 9 months |
Consumer | Retail loans: | Consumer Loan |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  | 10 years | 10 years 11 months 5 days | 9 years 11 months 9 days | 10 years 9 months |
Payment Delay |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Minimum period loan terms were extended |  | 90 days | 90 days | 90 days | 90 days |
Subsequent default during period |  | $ 0 |  | $ 0 |  |
Interest Rate Reduction |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Minimum period loan terms were extended |  | 90 days | 90 days | 90 days | 90 days |
Subsequent default during period |  | $ 0 |  | $ 0 |  |
[1] | Primarily loans secured by owner-occupied real estate.

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