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Loans (Recorded Investment By Loan Class In Current And Nonaccrual Loans) (Details) - USD ($) $ in Thousands | Sep. 30, 2019 | Dec. 31, 2018 | Sep. 30, 2018
--- | --- | --- | ---
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | $ 5,483 | $ 5,713 |
Nonaccrual | 9,785 | 7,133 |
Current | 3,099,465 | 3,031,474 |
Total Loans | 3,114,733 | 3,044,320 | $ 2,946,668
30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 4,629 | 4,761 |
60 to 89 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 851 | 944 |
Greater than 90 Days [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 3 | 8 |
Commercial Business [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 628 | 228 |
Nonaccrual | 2,884 | 912 |
Current | 570,098 | 555,900 |
Total Loans | 573,610 | 557,040 | 537,160
Commercial Business [Member] | 30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 628 | 227 |
Commercial Business [Member] | 60 to 89 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans |  | 1 |
Commercial Mortgage [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 286 | 574 |
Nonaccrual | 2,867 | 1,586 |
Current | 1,034,151 | 958,105 |
Total Loans | 1,037,304 | 960,265 | 907,107
Commercial Mortgage [Member] | 30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 286 | 574 |
Residential Real Estate Loans [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 1,004 | 1,537 |
Nonaccrual | 2,526 | 2,391 |
Current | 544,309 | 511,053 |
Total Loans | 547,839 | 514,981 | 498,883
Residential Real Estate Loans [Member] | 30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 797 | 1,295 |
Residential Real Estate Loans [Member] | 60 to 89 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 207 | 242 |
Residential Real Estate Lines [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 219 | 102 |
Nonaccrual | 182 | 255 |
Current | 104,144 | 106,355 |
Total Loans | 104,545 | 106,712 | 108,227
Residential Real Estate Lines [Member] | 30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 173 | 102 |
Residential Real Estate Lines [Member] | 60 to 89 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 46 |  |
Consumer Indirect [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 3,264 | 3,122 |
Nonaccrual | 1,326 | 1,989 |
Current | 830,378 | 883,621 |
Total Loans | 834,968 | 888,732 | 878,316
Consumer Indirect [Member] | 30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 2,672 | 2,424 |
Consumer Indirect [Member] | 60 to 89 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 592 | 698 |
Other Consumer [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 82 | 150 |
Current | 16,385 | 16,440 |
Total Loans | 16,467 | 16,590 | $ 16,975
Other Consumer [Member] | 30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 73 | 139 |
Other Consumer [Member] | 60 to 89 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 6 | 3 |
Other Consumer [Member] | Greater than 90 Days [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | $ 3 | $ 8 |

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