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Loans And Allowance For Credit Losses (Summary Classification Of Held To Maturity Loan Portfolio) (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Dec. 31, 2024
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Loans And Allowance For Loan Losses [Line Items] |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | $ 17,665,468 | $ 17,220,103
Business Loan [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 6,328,684 | 6,053,820
Real estate - construction and land |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 1,405,398 | 1,409,901
Business Real Estate Loan [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 3,757,778 | 3,661,218
Personal Real Estate Loan [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 3,058,845 | 3,058,195
Consumer Loan [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 2,157,867 | 2,073,123
Revolving home equity |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 364,429 | 356,650
Credit Card Receivable [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 576,151 | 595,930
Overdrafts |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | $ 16,316 | $ 11,266

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