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Credit Quality And Allowance For Credit Losses (Narrative) (Details) - USD ($)
$ in Millions

3 Months Ended

6 Months Ended

Jun. 30, 2024

Jun. 30, 2023

Jun. 30, 2024

Jun. 30, 2023

Dec. 31, 2023

Financing Receivable, Troubled Debt Restructuring [Line Items]

Loan interest receivable

$ 274

$ 274

$ 313

Interest income

6

$ 2

8

$ 6

Commitments to lend additional funds to TDR borrowers

$ 0

$ 0

$ 0

Weighted-Average Term Extension (in months)

1 year 11 days

11 months 16 days

1 year 22 days

1 year 1 month 24 days

Business loans:

Financing Receivable, Troubled Debt Restructuring [Line Items]

Weighted-Average Term Extension (in months)

1 year 11 days

11 months 16 days

11 months 27 days

1 year 1 month 24 days

Commercial | Other business lines | Commercial mortgage:

Financing Receivable, Troubled Debt Restructuring [Line Items]

Weighted-Average Term Extension (in months)

^[1]

2 years 7 months 28 days

Commercial | Business loans:

Financing Receivable, Troubled Debt Restructuring [Line Items]

Weighted-Average Term Extension (in months)

1 year 1 month 6 days

6 months 18 days

1 year 11 days

9 months 7 days

Commercial | Business loans: | International

Financing Receivable, Troubled Debt Restructuring [Line Items]

Weighted-Average Term Extension (in months)

7 months 28 days

8 months 19 days

Commercial | Business loans: | Commercial mortgage:

Financing Receivable, Troubled Debt Restructuring [Line Items]

Weighted-Average Term Extension (in months)

7 months 6 days

5 years 4 days

9 months

2 years 5 months 16 days

Commercial | Business loans: | Commercial | Commercial mortgage:

Financing Receivable, Troubled Debt Restructuring [Line Items]

Weighted-Average Term Extension (in months)

^[2]

6 months

Commercial | Business loans: | Other business lines | Commercial mortgage:

Financing Receivable, Troubled Debt Restructuring [Line Items]

Weighted-Average Term Extension (in months)

^[1]

7 months 6 days

5 years 4 days

9 months

Consumer | Retail loans:

Financing Receivable, Troubled Debt Restructuring [Line Items]

Weighted-Average Term Extension (in months)

9 years 10 months 10 days

Consumer | Retail loans: | Home equity

Financing Receivable, Troubled Debt Restructuring [Line Items]

Weighted-Average Term Extension (in months)

9 years 10 months 10 days

Consumer | Retail loans: | Consumer Loan

Financing Receivable, Troubled Debt Restructuring [Line Items]

Weighted-Average Term Extension (in months)

9 years 10 months 10 days

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.
[2]	Primarily loans to real estate developers.

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