Loans (Loan Modifications Made To Borrowers Experiencing Financial Difficulty) (Details) $ in Millions	12 Months Ended
Dec. 31, 2023 USD ($)
Financing Receivable, Troubled Debt Restructuring [Line Items]
AMORTIZED COST BASIS	$ 40.7
% OF TOTAL SEGMENT	0.09%
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
AMORTIZED COST BASIS	$ 16.7
% OF TOTAL SEGMENT	0.07%
Commercial \| Commercial and Institutional \| Term extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
AMORTIZED COST BASIS	$ 16.7
% OF TOTAL SEGMENT	0.14%
Financing receivable, modified, weighted average term increase from modification	12 months
Commercial \| Commercial Real Estate \| Combination of principal and/or interest deferral and term extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
AMORTIZED COST BASIS	$ 0.0
% OF TOTAL SEGMENT	0.00%
Commercial \| Commercial Real Estate \| Principal and/or interest deferral
Financing Receivable, Troubled Debt Restructuring [Line Items]
AMORTIZED COST BASIS	$ 0.0
% OF TOTAL SEGMENT	0.00%
Financing receivable, excluding accrued interest, modified, deferred interest and principal	$ 32.5
Financing receivable, modified, weighted average term increase from modification	6 months
Commercial \| Commercial Real Estate \| Term extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, weighted average term increase from modification	6 months
Personal
Financing Receivable, Troubled Debt Restructuring [Line Items]
AMORTIZED COST BASIS	$ 24.0
% OF TOTAL SEGMENT	0.11%
Personal \| Residential Real Estate \| Combination of principal and/or interest deferral and term extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
AMORTIZED COST BASIS	$ 4.7
% OF TOTAL SEGMENT	0.07%
Personal \| Residential Real Estate \| Principal and/or interest deferral
Financing Receivable, Troubled Debt Restructuring [Line Items]
AMORTIZED COST BASIS	$ 1.0
% OF TOTAL SEGMENT	0.02%
Financing receivable, modified, weighted average term increase from modification	14 months
Personal \| Residential Real Estate \| Term extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, modified, weighted average term increase from modification	9 months
Personal \| Residential Real Estate \| Interest rate concession
Financing Receivable, Troubled Debt Restructuring [Line Items]
AMORTIZED COST BASIS	$ 0.0
% OF TOTAL SEGMENT	0.00%
Financing receivable, modified, weighted average interest rate decrease from modification	2.00%
Personal \| Private Client \| Principal and/or interest deferral
Financing Receivable, Troubled Debt Restructuring [Line Items]
AMORTIZED COST BASIS	$ 18.3
% OF TOTAL SEGMENT	0.13%
Financing receivable, excluding accrued interest, modified, deferred interest and principal	$ 18.9
Personal \| Private Client \| Term extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
AMORTIZED COST BASIS	$ 0.0
% OF TOTAL SEGMENT	0.00%
Financing receivable, modified, weighted average term increase from modification	60 months

Financing Receivable, Excluding Accrued Interest, Modified, Financially Distressed

No definition available.

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- Definition

Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty.

+ References

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- Definition

Percentage, excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables.

+ References

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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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.

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