Days that a principal or interest payment is past due to be defined as a subsequent default

No definition available.

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- Definition

Financial Receivable, Troubled Debt Restructuring, Other-than-Insignificant Payment Delays

+ References

No definition available.

+ Details

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- Definition

Loan interest receivable

+ References

No definition available.

+ 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

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+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amortized cost of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
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- Definition

Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Definition

Amount of commitment to lend additional funds to debtor experiencing financial difficulty for which creditor has modified terms of financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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Period Type:	instant

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- Details

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- Details

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Credit Quality And Allowance For Credit Losses (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loan interest receivable	$ 317		$ 317		$ 261
Commitments to lend additional funds to TDR borrowers	$ 0	$ 1	$ 0	$ 1
Weighted-Average Term Extension (in months)	9 years 2 months 12 days		11 years
Domestic
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructuring, other-than-insignificant payment delays			$ 5
Business loans:
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in months)	7 years 4 months 24 days		9 years 8 months 12 days
Commercial \| Business loans:
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in months)	7 years 4 months 24 days		8 years
Commercial \| Business loans: \| Commercial mortgage:
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in months)	8 years 8 months 12 days		22 years
Commercial \| Business loans: \| Real estate construction:
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in months)	6 years		6 years
Commercial \| Business loans: \| Other business lines \| Commercial mortgage:
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in months)	8 years 8 months 12 days		22 years
Commercial \| Business loans: \| Other business lines \| Real estate construction:
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in months)	6 years		6 years
Consumer \| Retail loans:
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in months)	131 years 1 month 6 days		129 years
Consumer \| Retail loans: \| Home equity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in months)	131 years 1 month 6 days		129 years
Consumer \| Retail loans: \| Consumer:
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in months)	131 years 1 month 6 days		129 years
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	$ 6
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	$ 0