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Loans (Recorded Investment by Loan Class in Current and Nonaccrual Loans) (Details) - USD ($) $ in Thousands | Jun. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | $ 5,000 | $ 7,994
Investment securities, nonaccrual | 6,593 | 9,286
Current | 3,580,246 | 3,540,628
Total Loans | 3,591,839 | 3,557,908
Nonaccrual with no allowance | 5,407 | 8,616
30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 4,416 | 6,209
60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 542 | 1,554
Greater than 90 Days [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 42 | 231
Commercial Business [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 80 | 351
Investment securities, nonaccrual | 1,555 | 1,975
Current | 734,293 | 796,083
Total Loans | 735,928 | 798,409
Nonaccrual with no allowance | 899 | 1,502
Commercial Business [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 80 | 264
Commercial Business [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans |  | 87
Commercial Mortgage [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 900 | 848
Investment securities, nonaccrual | 885 | 2,906
Current | 1,315,969 | 1,252,771
Total Loans | 1,317,754 | 1,256,525
Nonaccrual with no allowance | 355 | 2,709
Commercial Mortgage [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 900 | 822
Commercial Mortgage [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans |  | 26
Residential Real Estate Loans [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 628 | 1,044
Investment securities, nonaccrual | 2,615 | 2,587
Current | 573,389 | 582,906
Total Loans | 576,632 | 586,537
Nonaccrual with no allowance | 2,615 | 2,587
Residential Real Estate Loans [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 612 | 984
Residential Real Estate Loans [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 16 | 60
Residential Real Estate Lines [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 116 | 55
Investment securities, nonaccrual | 280 | 323
Current | 77,377 | 86,330
Total Loans | 77,773 | 86,708
Nonaccrual with no allowance | 280 | 323
Residential Real Estate Lines [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 116 | 40
Residential Real Estate Lines [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans |  | 15
Consumer Indirect [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 3,145 | 5,314
Investment securities, nonaccrual | 1,250 | 1,495
Current | 864,035 | 806,007
Total Loans | 868,430 | 812,816
Nonaccrual with no allowance | 1,250 | 1,495
Consumer Indirect [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 2,643 | 3,966
Consumer Indirect [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 502 | 1,348
Other Consumer [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 131 | 382
Investment securities, nonaccrual | 8 |
Current | 15,183 | 16,531
Total Loans | 15,322 | 16,913
Nonaccrual with no allowance | 8 |
Other Consumer [Member] | 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 65 | 133
Other Consumer [Member] | 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | 24 | 18
Other Consumer [Member] | Greater than 90 Days [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Past Due Loans | $ 42 | $ 231

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