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Loans (Recorded Investment by Loan Class in Current and Nonaccrual Loans) (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | $ 4,553,278 | $ 4,479,204
Financing Receivable, Allowance for Credit Loss, Current | 4,463,702 | 4,378,086
Investment securities, nonaccrual | 39,982 | 41,363
Nonaccrual with no allowance | 29,962 | 35,361
30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 10,532 | 17,197
60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 2,157 | 4,790
Greater than 90 Days [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 36 | 43
Total Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 12,725 | 22,030
Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 4,516,409 | 4,441,479
Commercial Business [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 709,101 | 665,321
Financing Receivable, Allowance for Credit Loss, Current | 702,454 | 658,927
Investment securities, nonaccrual | 5,672 | 5,609
Nonaccrual with no allowance | 356 | 427
Commercial Business [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 373 | 293
Commercial Business [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 199 | 9
Commercial Business [Member] | Greater than 90 Days [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 8
Commercial Business [Member] | Total Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 572 | 310
Commercial Business [Member] | Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 708,698 | 664,846
Commercial Mortgage [Member] | Construction [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 566,359 | 582,619
Financing Receivable, Allowance for Credit Loss, Current | 545,968 | 561,731
Investment securities, nonaccrual | 19,684 | 20,280
Nonaccrual with no allowance | 19,460 | 19,460
Commercial Mortgage [Member] | Multifamily [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 475,867 | 470,954
Financing Receivable, Allowance for Credit Loss, Current | 476,181 | 471,499
Investment securities, nonaccrual | 0 | 0
Nonaccrual with no allowance | 0 | 0
Commercial Mortgage [Member] | Non-Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 899,679 | 857,987
Financing Receivable, Allowance for Credit Loss, Current | 895,833 | 854,050
Investment securities, nonaccrual | 4,766 | 4,773
Nonaccrual with no allowance | 286 | 4,773
Commercial Mortgage [Member] | Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 286,391 | 288,036
Financing Receivable, Allowance for Credit Loss, Current | 286,072 | 287,688
Investment securities, nonaccrual | 349 | 354
Nonaccrual with no allowance | 349 | 354
Commercial Mortgage [Member] | 30 to 59 Days Past Due [Member] | Construction [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 2,329 | 0
Commercial Mortgage [Member] | 30 to 59 Days Past Due [Member] | Multifamily [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 219 | 0
Commercial Mortgage [Member] | 30 to 59 Days Past Due [Member] | Non-Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 244 | 256
Commercial Mortgage [Member] | 30 to 59 Days Past Due [Member] | Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Commercial Mortgage [Member] | 60 to 89 Days Past Due [Member] | Construction [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 2,285
Commercial Mortgage [Member] | 60 to 89 Days Past Due [Member] | Multifamily [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Commercial Mortgage [Member] | 60 to 89 Days Past Due [Member] | Non-Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Commercial Mortgage [Member] | 60 to 89 Days Past Due [Member] | Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Commercial Mortgage [Member] | Greater than 90 Days [Member] | Construction [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Commercial Mortgage [Member] | Greater than 90 Days [Member] | Multifamily [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Commercial Mortgage [Member] | Greater than 90 Days [Member] | Non-Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Commercial Mortgage [Member] | Greater than 90 Days [Member] | Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Commercial Mortgage [Member] | Total Past Due [Member] | Construction [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 2,329 | 2,285
Commercial Mortgage [Member] | Total Past Due [Member] | Multifamily [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 219 | 0
Commercial Mortgage [Member] | Total Past Due [Member] | Non-Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 244 | 256
Commercial Mortgage [Member] | Total Past Due [Member] | Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Commercial Mortgage [Member] | Total Loans [Member] | Construction [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 567,981 | 584,296
Commercial Mortgage [Member] | Total Loans [Member] | Multifamily [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 476,400 | 471,499
Commercial Mortgage [Member] | Total Loans [Member] | Non-Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 900,843 | 859,079
Commercial Mortgage [Member] | Total Loans [Member] | Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 286,421 | 288,042
Residential Real Estate Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 643,983 | 650,206
Financing Receivable, Allowance for Credit Loss, Current | 625,928 | 629,018
Investment securities, nonaccrual | 6,035 | 6,918
Nonaccrual with no allowance | 6,035 | 6,918
Residential Real Estate Loans [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 1,725 | 3,435
Residential Real Estate Loans [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 62 | 95
Residential Real Estate Loans [Member] | Greater than 90 Days [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Residential Real Estate Loans [Member] | Total Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 1,787 | 3,530
Residential Real Estate Loans [Member] | Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 633,750 | 639,466
Residential Real Estate Lines [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 74,769 | 75,552
Financing Receivable, Allowance for Credit Loss, Current | 71,065 | 71,638
Investment securities, nonaccrual | 316 | 253
Nonaccrual with no allowance | 316 | 253
Residential Real Estate Lines [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 96 | 370
Residential Real Estate Lines [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 85 | 47
Residential Real Estate Lines [Member] | Greater than 90 Days [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Residential Real Estate Lines [Member] | Total Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 181 | 417
Residential Real Estate Lines [Member] | Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 71,562 | 72,308
Consumer Indirect [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 853,176 | 845,772
Financing Receivable, Allowance for Credit Loss, Current | 816,894 | 801,006
Investment securities, nonaccrual | 2,917 | 3,157
Nonaccrual with no allowance | 2,917 | 3,157
Consumer Indirect [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 5,257 | 12,734
Consumer Indirect [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 1,662 | 2,219
Consumer Indirect [Member] | Greater than 90 Days [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Consumer Indirect [Member] | Total Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 6,919 | 14,953
Consumer Indirect [Member] | Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 826,730 | 819,116
Other Consumer [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 43,953 | 42,757
Financing Receivable, Allowance for Credit Loss, Current | 43,307 | 42,529
Investment securities, nonaccrual | 243 | 19
Nonaccrual with no allowance | 243 | 19
Other Consumer [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 289 | 109
Other Consumer [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 149 | 135
Other Consumer [Member] | Greater than 90 Days [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 36 | 35
Other Consumer [Member] | Total Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 474 | 279
Other Consumer [Member] | Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | $ 44,024 | $ 42,827

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