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COMMITMENTS, CONTINGENT LIABILITIES AND RESTRICTIONS (Tables) | 12 Months Ended
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Dec. 31, 2017
COMMITMENTS, CONTINGENT LIABILITIES AND RESTRICTIONS [Abstract] |
Off Balance Sheet Financial Instruments Contract Amounts | The contract amounts of commitments and contingencies are as follows at December 31:
(000's omitted) |  | 2017 |  |  | 2016 |
Commitments to extend credit |  | $ | 1,080,004 |  |  | $ | 773,442 |
Standby letters of credit |  |  | 23,782 |  |  |  | 22,656 |
Total |  | $ | 1,103,786 |  |  | $ | 796,098 |

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