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Loans (Recorded Investment By Loan Class In Current And Nonaccrual Loans) (Details) - USD ($) $ in Thousands | Mar. 31, 2018 | Dec. 31, 2017 | Mar. 31, 2017
--- | --- | --- | ---
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | $ 3,579 | $ 6,522 |
Nonaccrual | 10,700 | 12,520 |
Current | 2,738,171 | 2,675,880 |
Total loans | 2,752,450 | 2,694,922 | $ 2,366,640
30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 3,069 | 5,357 |
60 to 89 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 493 | 1,154 |
Greater than 90 Days [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 17 | 11 |
Commercial Business [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 127 | 100 |
Nonaccrual | 4,312 | 5,344 |
Current | 459,087 | 444,319 |
Total loans | 463,526 | 449,763 | 374,992
Commercial Business [Member] | 30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 127 | 64 |
Commercial Business [Member] | 60 to 89 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans |  | 36 |
Commercial Mortgage [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 388 | 431 |
Nonaccrual | 2,310 | 2,623 |
Current | 820,607 | 807,797 |
Total loans | 823,305 | 810,851 | 676,455
Commercial Mortgage [Member] | 30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 388 | 56 |
Commercial Mortgage [Member] | 60 to 89 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans |  | 375 |
Residential Real Estate Loans [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 963 | 1,964 |
Nonaccrual | 2,224 | 2,252 |
Current | 466,924 | 453,545 |
Total loans | 470,111 | 457,761 | 421,614
Residential Real Estate Loans [Member] | 30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 853 | 1,908 |
Residential Real Estate Loans [Member] | 60 to 89 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 110 | 56 |
Residential Real Estate Lines [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 167 | 349 |
Nonaccrual | 372 | 404 |
Current | 111,889 | 112,669 |
Total loans | 112,428 | 113,422 | 118,056
Residential Real Estate Lines [Member] | 30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 167 | 349 |
Consumer Indirect [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 1,813 | 3,478 |
Nonaccrual | 1,467 | 1,895 |
Current | 863,318 | 840,309 |
Total loans | 866,598 | 845,682 | 758,761
Consumer Indirect [Member] | 30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 1,443 | 2,806 |
Consumer Indirect [Member] | 60 to 89 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 370 | 672 |
Other Consumer [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 121 | 200 |
Nonaccrual | 15 | 2 |
Current | 16,346 | 17,241 |
Total loans | 16,482 | 17,443 | $ 16,762
Other Consumer [Member] | 30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 91 | 174 |
Other Consumer [Member] | 60 to 89 Days Past Due [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | 13 | 15 |
Other Consumer [Member] | Greater than 90 Days [Member] |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |
Past Due Loans | $ 17 | $ 11 |

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