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Loans (Recorded Investment By Loan Class In Current And Nonaccrual Loans) (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | --- | ---
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | $ 7,081 | $ 5,713 |
Nonaccrual | 8,634 | 7,133 |
Current | 3,163,750 | 3,031,474 |
Total Loans | 3,179,465 | 3,044,320 | $ 2,694,922
Commercial Business [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 361 | 228 |
Nonaccrual | 1,177 | 912 |
Current | 569,684 | 555,900 |
Total Loans | 571,222 | 557,040 | 449,763
Commercial Mortgage [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 531 | 574 |
Nonaccrual | 3,146 | 1,586 |
Current | 1,104,638 | 958,105 |
Total Loans | 1,108,315 | 960,265 | 810,851
Residential Real Estate Loans [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 1,043 | 1,537 |
Nonaccrual | 2,484 | 2,391 |
Current | 557,190 | 511,053 |
Total Loans | 560,717 | 514,981 | 457,761
Residential Real Estate Lines [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 268 | 102 |
Nonaccrual | 102 | 255 |
Current | 100,678 | 106,355 |
Total Loans | 101,048 | 106,712 | 113,422
Consumer Indirect [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 4,748 | 3,122 |
Nonaccrual | 1,725 | 1,989 |
Current | 815,706 | 883,621 |
Total Loans | 822,179 | 888,732 | 845,682
Other Consumer [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 130 | 150 |
Current | 15,854 | 16,440 |
Total Loans | 15,984 | 16,590 | $ 17,443
30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 5,897 | 4,761 |
30 to 59 Days Past Due [Member] | Commercial Business [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 361 | 227 |
30 to 59 Days Past Due [Member] | Commercial Mortgage [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 531 | 574 |
30 to 59 Days Past Due [Member] | Residential Real Estate Loans [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 929 | 1,295 |
30 to 59 Days Past Due [Member] | Residential Real Estate Lines [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 231 | 102 |
30 to 59 Days Past Due [Member] | Consumer Indirect [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 3,729 | 2,424 |
30 to 59 Days Past Due [Member] | Other Consumer [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 116 | 139 |
60 to 89 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 1,178 | 944 |
60 to 89 Days Past Due [Member] | Commercial Business [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans |  | 1 |
60 to 89 Days Past Due [Member] | Residential Real Estate Loans [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 114 | 242 |
60 to 89 Days Past Due [Member] | Residential Real Estate Lines [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 37 |  |
60 to 89 Days Past Due [Member] | Consumer Indirect [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 1,019 | 698 |
60 to 89 Days Past Due [Member] | Other Consumer [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 8 | 3 |
Greater than 90 Days [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 6 | 8 |
Greater than 90 Days [Member] | Other Consumer [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | $ 6 | $ 8 |

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