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ACCUMULATED OTHER COMPREHENSIVE LOSS (Tables) | 12 Months Ended
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Dec. 31, 2019
ACCUMULATED OTHER COMPREHENSIVE LOSS |
Schedule of accumulated other comprehensive loss | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Unrealized | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Gain (Loss) | ​ | ​ | ​
​ | ​ | Pension | ​ | on | ​ | ​ | ​
​ |  | Adjustment |  | Securities |  | Total
(in thousands) |  | ​ |  |  | ​ |  |  | ​ |
Balance at December 31, 2017 | ​ | $ | (1,936) | ​ | $ | (44) | ​ | $ | (1,980)
Change during 2018: | ​ |  |  | ​ |  |  | ​ |  | ​
Before-tax amount | ​ |  | (390) | ​ |  | (20) | ​ |  | (410)
Tax expense | ​ |  | 85 | ​ |  | 4 | ​ |  | 89
Reclassification adjustment, net of taxes | ​ |  |  | ​ |  |  | ​ |  |
Amortization of net loss | ​ |  | 63 | ​ |  | — | ​ |  | 63
Net realized gain | ​ |  | — | ​ |  | 63 | ​ |  | 63
Total activity in 2018 | ​ |  | (242) | ​ |  | 47 | ​ |  | (195)
Balance at December 31, 2018 | ​ | $ | (2,178) | ​ | $ | 3 | ​ | $ | (2,175)
Change during 2019: | ​ |  |  | ​ |  |  | ​ |  |
Adoption of accounting standard (Note 1) | ​ | ​ | (404) | ​ | ​ | (10) | ​ | ​ | (414)
Before-tax amount | ​ |  | (300) | ​ |  | 13 | ​ |  | (287)
Tax benefit | ​ |  | 66 | ​ |  | (3) | ​ |  | 63
Reclassification adjustment, net of taxes | ​ |  |  | ​ |  |  | ​ |  |
Amortization of net loss | ​ |  | 68 | ​ |  | — | ​ |  | 68
Net realized loss | ​ |  | — | ​ |  | (3) | ​ |  | (3)
Total activity in 2019 | ​ |  | (570) | ​ |  | (3) | ​ |  | (573)
Balance at December 31, 2019 | ​ | $ | (2,748) | ​ | $ | — | ​ | $ | (2,748)

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