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Loans (Recorded Investment by Loan Class in Current and Nonaccrual Loans) (Details) - USD ($) $ in Thousands | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | $ 4,192,142 | $ 3,998,718
Investment securities, nonaccrual | 8,797 | 10,197
Nonaccrual with no allowance | 6,666 | 8,185
30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 7,838 | 14,494
60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 1,325 | 2,214
Greater than 90 Days [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 4 | 1
Total Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 9,167 | 16,709
Current [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 4,174,178 | 3,971,812
Commercial Business [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 694,427 | 663,611
Investment securities, nonaccrual | 334 | 340
Nonaccrual with no allowance | 233 | 233
Commercial Business [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 925 | 176
Commercial Business [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 10
Commercial Business [Member] | Greater than 90 Days [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Commercial Business [Member] | Total Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 925 | 186
Commercial Business [Member] | Current [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 693,168 | 663,085
Commercial Mortgage [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 1,845,762 | 1,683,814
Investment securities, nonaccrual | 2,550 | 2,564
Nonaccrual with no allowance | 520 | 659
Commercial Mortgage [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Commercial Mortgage [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Commercial Mortgage [Member] | Greater than 90 Days [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Commercial Mortgage [Member] | Total Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 0 | 0
Commercial Mortgage [Member] | Current [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 1,843,212 | 1,681,250
Residential Real Estate Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 578,363 | 576,279
Investment securities, nonaccrual | 3,267 | 4,071
Nonaccrual with no allowance | 3,267 | 4,071
Residential Real Estate Loans [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 778 | 1,306
Residential Real Estate Loans [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 49 | 28
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 | 827 | 1,334
Residential Real Estate Loans [Member] | Current [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 574,269 | 570,874
Residential Real Estate Lines [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 72,793 | 74,432
Investment securities, nonaccrual | 159 | 142
Nonaccrual with no allowance | 159 | 142
Residential Real Estate Lines [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 219 | 264
Residential Real Estate Lines [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 30 | 102
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 | 249 | 366
Residential Real Estate Lines [Member] | Current [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 72,385 | 73,924
Consumer Indirect [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 984,302 | 985,580
Investment securities, nonaccrual | 2,487 | 3,079
Nonaccrual with no allowance | 2,487 | 3,079
Consumer Indirect [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 5,812 | 12,637
Consumer Indirect [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 1,245 | 2,073
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 | 7,057 | 14,710
Consumer Indirect [Member] | Current [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 974,758 | 967,791
Other Consumer [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 16,495 | 15,002
Investment securities, nonaccrual | 0 | 1
Nonaccrual with no allowance | 0 | 1
Other Consumer [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 104 | 111
Other Consumer [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 1 | 1
Other Consumer [Member] | Greater than 90 Days [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 4 | 1
Other Consumer [Member] | Total Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | 109 | 113
Other Consumer [Member] | Current [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Loans | $ 16,386 | $ 14,888

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