Credit Quality And Allowance For Credit Losses (Financial Effect of Loan Modifications) (Details)	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2023
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in months)	9 years 2 months 12 days	11 years
Weighted-Average Interest Rate Reduction	(1.09%)	(0.89%)
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
Weighted-Average Interest Rate Reduction	(0.81%)	(0.70%)
Business loans: \| Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in months)	7 years 4 months 24 days	8 years
Weighted-Average Interest Rate Reduction	(0.50%)	(0.49%)
Retail loans: \| Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in months)	131 years 1 month 6 days	129 years
Weighted-Average Interest Rate Reduction	(2.85%)	(2.64%)
Commercial mortgage: \| Business loans: \| Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in months)	8 years 8 months 12 days	22 years
Weighted-Average Interest Rate Reduction	(1.00%)	(0.79%)
Commercial mortgage: \| Business loans: \| Commercial \| Other business lines
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in months)	8 years 8 months 12 days	22 years
Weighted-Average Interest Rate Reduction	(1.00%)	(0.79%)
Home equity \| Retail loans: \| Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in months)	131 years 1 month 6 days	129 years
Weighted-Average Interest Rate Reduction	(2.85%)	(2.64%)
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
Weighted-Average Interest Rate Reduction	(2.85%)	(2.64%)
Real estate construction: \| Business loans: \| Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in months)	6 years	6 years
Real estate construction: \| Business loans: \| Commercial \| Other business lines
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-Average Term Extension (in months)	6 years	6 years

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.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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