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Loans (Recorded Investment by Loan Class in Current and Nonaccrual Loans) (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | $ 4,402,989 | $ 4,462,139
Financing Receivable, Allowance for Credit Loss, Current | 4,303,551 | 4,360,265
Investment securities, nonaccrual | 40,699 | 26,639
Nonaccrual with no allowance | 34,958 | 21,316
30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 10,350 | 25,268
60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 8,558 | 4,058
Greater than 90 Days [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 43 | 21
Total Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 18,951 | 29,347
Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 4,363,201 | 4,416,251
Commercial Business [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 654,519 | 735,700
Financing Receivable, Allowance for Credit Loss, Current | 641,654 | 728,942
Investment securities, nonaccrual | 5,752 | 5,664
Nonaccrual with no allowance | 332 | 341
Commercial Business [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 7 | 341
Commercial Business [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 6,500 | 0
Commercial Business [Member] | Greater than 90 Days [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 8 | 0
Commercial Business [Member] | Total Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 6,515 | 341
Commercial Business [Member] | Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 653,921 | 734,947
Commercial Mortgage [Member] | Construction [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 533,506 | 493,003
Financing Receivable, Allowance for Credit Loss, Current | 514,792 | 489,151
Investment securities, nonaccrual | 20,280 | 5,320
Nonaccrual with no allowance | 20,280 | 5,320
Commercial Mortgage [Member] | Multifamily [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 467,527 | 452,155
Financing Receivable, Allowance for Credit Loss, Current | 467,993 | 448,553
Investment securities, nonaccrual | 71 | 189
Nonaccrual with no allowance | 71 | 189
Commercial Mortgage [Member] | Non-Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 814,392 | 788,515
Financing Receivable, Allowance for Credit Loss, Current | 810,132 | 784,642
Investment securities, nonaccrual | 4,903 | 4,651
Nonaccrual with no allowance | 4,582 | 4,651
Commercial Mortgage [Member] | Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 290,216 | 271,646
Financing Receivable, Allowance for Credit Loss, Current | 289,855 | 269,733
Investment securities, nonaccrual | 366 | 403
Nonaccrual with no allowance | 366 | 403
Commercial Mortgage [Member] | 30 to 59 Days Past Due [Member] | Construction [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 52 | 0
Commercial Mortgage [Member] | 30 to 59 Days Past Due [Member] | Multifamily [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 4,036
Commercial Mortgage [Member] | 30 to 59 Days Past Due [Member] | Non-Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 334 | 338
Commercial Mortgage [Member] | 30 to 59 Days Past Due [Member] | Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 1,526
Commercial Mortgage [Member] | 60 to 89 Days Past Due [Member] | Construction [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 727
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 | 52 | 727
Commercial Mortgage [Member] | Total Past Due [Member] | Multifamily [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 4,036
Commercial Mortgage [Member] | Total Past Due [Member] | Non-Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 334 | 338
Commercial Mortgage [Member] | Total Past Due [Member] | Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 1,526
Commercial Mortgage [Member] | Total Loans [Member] | Construction [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 535,124 | 495,198
Commercial Mortgage [Member] | Total Loans [Member] | Multifamily [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 468,064 | 452,778
Commercial Mortgage [Member] | Total Loans [Member] | Non-Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 815,369 | 789,631
Commercial Mortgage [Member] | Total Loans [Member] | Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 290,221 | 271,662
Residential Real Estate Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 648,241 | 649,822
Financing Receivable, Allowance for Credit Loss, Current | 628,724 | 628,115
Investment securities, nonaccrual | 5,790 | 6,364
Nonaccrual with no allowance | 5,790 | 6,364
Residential Real Estate Loans [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 2,356 | 2,614
Residential Real Estate Loans [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 80
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 | 2,356 | 2,694
Residential Real Estate Loans [Member] | Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 636,870 | 637,173
Residential Real Estate Lines [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 76,203 | 77,367
Financing Receivable, Allowance for Credit Loss, Current | 72,564 | 73,568
Investment securities, nonaccrual | 232 | 221
Nonaccrual with no allowance | 232 | 221
Residential Real Estate Lines [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 81 | 163
Residential Real Estate Lines [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 49 | 20
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 | 130 | 183
Residential Real Estate Lines [Member] | Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 72,926 | 73,972
Consumer Indirect [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 874,651 | 948,831
Financing Receivable, Allowance for Credit Loss, Current | 834,330 | 892,577
Investment securities, nonaccrual | 3,291 | 3,814
Nonaccrual with no allowance | 3,291 | 3,814
Consumer Indirect [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 7,284 | 16,128
Consumer Indirect [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 1,998 | 3,204
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 | 9,282 | 19,332
Consumer Indirect [Member] | Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 846,903 | 915,723
Other Consumer [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 43,734 | 45,100
Financing Receivable, Allowance for Credit Loss, Current | 43,507 | 44,984
Investment securities, nonaccrual | 14 | 13
Nonaccrual with no allowance | 14 | 13
Other Consumer [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 236 | 122
Other Consumer [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 11 | 27
Other Consumer [Member] | Greater than 90 Days [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 35 | 21
Other Consumer [Member] | Total Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 282 | 170
Other Consumer [Member] | Total Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | $ 43,803 | $ 45,167

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