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ACCUMULATED OTHER COMPREHENSIVE INCOME OR LOSS | 12 Months Ended
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Dec. 31, 2017
Equity [Abstract] |
ACCUMULATED OTHER COMPREHENSIVE INCOME OR LOSS | ACCUMULATED OTHER COMPREHENSIVE INCOME OR LOSS Accumulated other comprehensive income or loss represents the net unrealized holding gains or losses on securities available for sale and the funded status of the Corporation's defined benefit pension plan and other benefit plans, as of the consolidated balance sheet dates, net of the related tax effect. The following is a summary of the changes in accumulated other comprehensive income or loss by component, net of tax, for the periods indicated (in thousands):
|  | Unrealized Gains and Losses on Securities Available for Sale |  | Defined Benefit and Other Benefit Plans |  | Total
Balance at December 31, 2016 |  | $ | (4,356 | ) |  | $ | (6,398 | ) |  | $ | (10,754 | )
Other comprehensive income before reclassification |  | 1,578 |  |  | 622 |  |  | 2,200 |
Amounts reclassified from accumulated other comprehensive income (loss) |  | (68 | ) |  | 119 |  |  | 51 |
Net current period other comprehensive income |  | 1,510 |  |  | 741 |  |  | 2,251 |
Stranded AOCI reclassification |  | (569 | ) |  | (1,268 | ) |  | (1,837 | )
Balance at December 31, 2017 |  | $ | (3,415 | ) |  | $ | (6,925 | ) |  | $ | (10,340 | )
|  | Unrealized Gains and Losses on Securities Available for Sale |  | Defined Benefit and Other Benefit Plans |  | Total
Balance at December 31, 2015 |  | $ | 210 |  |  | $ | (11,152 | ) |  | $ | (10,942 | )
Other comprehensive income (loss) before reclassification |  | (3,952 | ) |  | 3,341 |  |  | (611 | )
Amounts reclassified from accumulated other comprehensive income (loss) |  | (614 | ) |  | 1,413 |  |  | 799 |
Net current period other comprehensive income (loss) |  | (4,566 | ) |  | 4,754 |  |  | 188 |
Balance at December 31, 2016 |  | $ | (4,356 | ) |  | $ | (6,398 | ) |  | $ | (10,754 | )
|  | Unrealized Gains and Losses on Securities Available for Sale |  | Defined Benefit and Other Benefit Plans |  | Total
Balance at January 1, 2015 |  | $ | 1,960 |  |  | $ | (10,745 | ) |  | $ | (8,785 | )
Other comprehensive income (loss) before reclassification |  | (1,520 | ) |  | (1,268 | ) |  | (2,788 | )
Amounts reclassified from accumulated other comprehensive income (loss) |  | (230 | ) |  | 861 |  |  | 631 |
Net current period other comprehensive loss |  | (1,750 | ) |  | (407 | ) |  | (2,157 | )
Balance at December 31, 2015 |  | $ | 210 |  |  | $ | (11,152 | ) |  | $ | (10,942 | )
The following is the reclassification out of accumulated other comprehensive income (loss) for the periods indicated (in thousands):
Details about Accumulated Other Comprehensive Income (Loss) Components |  | Year Ended December 31, |  | Affected Line Item in the Statement Where Net Income is Presented
|  | 2017 |  | 2016 |  | 2015 |  |
Unrealized gains and losses on securities available for sale: |  |  |  |  |  |  |  |
Realized gains on securities available for sale |  | $ | (109 | ) |  | $ | (987 | ) |  | $ | (372 | ) |  | Net gains on securities transactions
Tax effect |  | 41 |  |  | 373 |  |  | 142 |  |  | Income tax expense
Net of tax |  | (68 | ) |  | (614 | ) |  | (230 | ) |  |
Amortization of defined pension plan and other benefit plan items: |  |  |  |  |  |  |  |  |  |  |
Prior service costs (a) |  | (220 | ) |  | 674 |  |  | (90 | ) |  | Pension and other employee benefits
Actuarial losses (a) |  | 413 |  |  | 1,595 |  |  | 1,484 |  |  | Pension and other employee benefits
Tax effect |  | (74 | ) |  | (856 | ) |  | (533 | ) |  | Income tax expense
Net of tax |  | 119 |  |  | 1,413 |  |  | 861 |  |  |
Total reclassification for the period, net of tax |  | $ | 51 |  |  | $ | 799 |  |  | $ | 631 |  |  |
(a) These accumulated other comprehensive income (loss) components are included in the computation of net periodic pension and other benefit plan costs (see Note 12 for additional information).

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