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ACCUMULATED OTHER COMPREHENSIVE INCOME OR LOSS (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Summary of changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward] |  |  |
Beginning Balances | $ 143,748 | $ 137,242 | $ 133,628
Stranded AOCI reclassification | 0 |  |
Total other comprehensive income (loss) | 2,251 | 188 | (2,157)
Ending Balances | 149,813 | 143,748 | 137,242
Net gains on securities transactions | 109 | 987 | 372
Income tax expense | 7,262 | 4,404 | 4,658
Pension and other employee benefits | 4,276 | 6,132 | 5,908
Net of tax | 7,430 | 10,027 | 9,433
Reclassification out of Accumulated Other Comprehensive Income (loss) |  |  |
Summary of changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward] |  |  |
Net of tax | 51 | 799 | 631
Unrealized Gains and Losses on Securities Available for Sale |  |  |
Summary of changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward] |  |  |
Beginning Balances | (4,356) | 210 | 1,960
Other comprehensive income (loss) before reclassification | 1,578 | (3,952) | (1,520)
Amounts reclassified from accumulated other comprehensive income (loss) | (68) | (614) | (230)
Stranded AOCI reclassification | (569) |  |
Total other comprehensive income (loss) | 1,510 | (4,566) | (1,750)
Ending Balances | (3,415) | (4,356) | 210
Unrealized Gains and Losses on Securities Available for Sale | Reclassification out of Accumulated Other Comprehensive Income (loss) |  |  |
Summary of changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward] |  |  |
Net gains on securities transactions | (109) | (987) | (372)
Income tax expense | 41 | 373 | 142
Net of tax | (68) | (614) | (230)
Defined Benefit and Other Benefit Plans |  |  |
Summary of changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward] |  |  |
Beginning Balances | (6,398) | (11,152) | (10,745)
Other comprehensive income (loss) before reclassification | 622 | 3,341 | (1,268)
Amounts reclassified from accumulated other comprehensive income (loss) | 119 | 1,413 | 861
Stranded AOCI reclassification | (1,268) |  |
Total other comprehensive income (loss) | 741 | 4,754 | (407)
Ending Balances | (6,925) | (6,398) | (11,152)
Defined Benefit and Other Benefit Plans | Reclassification out of Accumulated Other Comprehensive Income (loss) |  |  |
Summary of changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward] |  |  |
Income tax expense | (74) | (856) | (533)
Net of tax | 119 | 1,413 | 861
Net Prior Service Cost (Credit) | Reclassification out of Accumulated Other Comprehensive Income (loss) |  |  |
Summary of changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward] |  |  |
Pension and other employee benefits | (220) | 674 | (90)
Net Unamortized Gain (Loss) | Reclassification out of Accumulated Other Comprehensive Income (loss) |  |  |
Summary of changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward] |  |  |
Pension and other employee benefits | 413 | 1,595 | 1,484
Accumulated Other Comprehensive Income (Loss) |  |  |
Summary of changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward] |  |  |
Beginning Balances | (10,754) | (10,942) | (8,785)
Other comprehensive income (loss) before reclassification | 2,200 | (611) | (2,788)
Amounts reclassified from accumulated other comprehensive income (loss) | 51 | 799 | 631
Stranded AOCI reclassification | (1,837) |  |
Total other comprehensive income (loss) | 2,251 | 188 | (2,157)
Ending Balances | $ (10,340) | $ (10,754) | $ (10,942)

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- Definition Tax Cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings, Tax Effect + References No definition available. + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition The net gain (loss) realized from the sale, exchange, redemption, or retirement of securities, not separately or otherwise categorized as trading, available-for-sale, or held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13(h)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.3) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 + Details
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a),(b) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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