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Loans (Recorded Investment by Loan Class in Current and Nonaccrual Loans) (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | $ 4,590,423 | $ 4,479,204
Financing Receivable, Allowance for Credit Loss, Current | 4,502,764 | 4,378,086
Investment securities, nonaccrual | 33,951 | 41,363
Nonaccrual with no allowance | 30,155 | 35,361
30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 14,437 | 17,197
60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 4,785 | 4,790
Greater than 90 Days [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 43
Total Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 19,222 | 22,030
Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 4,555,937 | 4,441,479
Commercial Business [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 740,603 | 665,321
Financing Receivable, Allowance for Credit Loss, Current | 735,836 | 658,927
Investment securities, nonaccrual | 3,799 | 5,609
Nonaccrual with no allowance | 538 | 427
Commercial Business [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 179 | 293
Commercial Business [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 7 | 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 | 186 | 310
Commercial Business [Member] | Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 739,821 | 664,846
Commercial Mortgage [Member] | Construction [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 441,034 | 582,619
Financing Receivable, Allowance for Credit Loss, Current | 421,515 | 561,731
Investment securities, nonaccrual | 19,794 | 20,280
Nonaccrual with no allowance | 19,794 | 19,460
Commercial Mortgage [Member] | Multifamily [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 592,634 | 470,954
Financing Receivable, Allowance for Credit Loss, Current | 588,679 | 471,499
Investment securities, nonaccrual | 540 | 0
Nonaccrual with no allowance | 540 | 0
Commercial Mortgage [Member] | Non-Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 893,884 | 857,987
Financing Receivable, Allowance for Credit Loss, Current | 895,038 | 854,050
Investment securities, nonaccrual | 0 | 4,773
Nonaccrual with no allowance | 0 | 4,773
Commercial Mortgage [Member] | Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 321,555 | 288,036
Financing Receivable, Allowance for Credit Loss, Current | 320,453 | 287,688
Investment securities, nonaccrual | 1,102 | 354
Nonaccrual with no allowance | 567 | 354
Commercial Mortgage [Member] | 30 to 59 Days Past Due [Member] | Construction [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Commercial Mortgage [Member] | 30 to 59 Days Past Due [Member] | Multifamily [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 4,161 | 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 | 0 | 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 | 2,417 | 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 | 2,417 | 2,285
Commercial Mortgage [Member] | Total Past Due [Member] | Multifamily [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 4,161 | 0
Commercial Mortgage [Member] | Total Past Due [Member] | Non-Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 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 | 443,726 | 584,296
Commercial Mortgage [Member] | Total Loans [Member] | Multifamily [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 593,380 | 471,499
Commercial Mortgage [Member] | Total Loans [Member] | Non-Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 895,038 | 859,079
Commercial Mortgage [Member] | Total Loans [Member] | Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 321,555 | 288,042
Residential Real Estate Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 648,397 | 650,206
Financing Receivable, Allowance for Credit Loss, Current | 631,186 | 629,018
Investment securities, nonaccrual | 5,877 | 6,918
Nonaccrual with no allowance | 5,877 | 6,918
Residential Real Estate Loans [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 1,897 | 3,435
Residential Real Estate Loans [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 126 | 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 | 2,023 | 3,530
Residential Real Estate Loans [Member] | Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 639,086 | 639,466
Residential Real Estate Lines [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 76,109 | 75,552
Financing Receivable, Allowance for Credit Loss, Current | 72,008 | 71,638
Investment securities, nonaccrual | 212 | 253
Nonaccrual with no allowance | 212 | 253
Residential Real Estate Lines [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 596 | 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 | 681 | 417
Residential Real Estate Lines [Member] | Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 72,901 | 72,308
Consumer Indirect [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 838,671 | 845,772
Financing Receivable, Allowance for Credit Loss, Current | 800,871 | 801,006
Investment securities, nonaccrual | 2,482 | 3,157
Nonaccrual with no allowance | 2,482 | 3,157
Consumer Indirect [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 7,471 | 12,734
Consumer Indirect [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 2,009 | 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 | 9,480 | 14,953
Consumer Indirect [Member] | Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 812,833 | 819,116
Other Consumer [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 37,536 | 42,757
Financing Receivable, Allowance for Credit Loss, Current | 37,178 | 42,529
Investment securities, nonaccrual | 145 | 19
Nonaccrual with no allowance | 145 | 19
Other Consumer [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 133 | 109
Other Consumer [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 141 | 135
Other Consumer [Member] | Greater than 90 Days [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 35
Other Consumer [Member] | Total Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 274 | 279
Other Consumer [Member] | Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | $ 37,597 | $ 42,827

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