ACCUMULATED OTHER COMPREHENSIVE INCOME OR LOSS - Summary of Changes in Accumulated Other Comprehensive Income or Loss by Component (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward]
Balances	$ 137,242	$ 133,628
Net current period other comprehensive gain	1,604	998
Balances	141,046	136,293
Accumulated Other Comprehensive Income (Loss) [Member]
Changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward]
Balances	(10,942)	(8,785)
Other comprehensive income before reclassification	1,936	805
Amounts reclassified from accumulated other comprehensive income	(332)	193
Net current period other comprehensive gain	1,604	998
Balances	(9,338)	(7,787)
Unrealized Gains and Losses on Securities Available for Sale [Member]
Changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward]
Balances	210	1,960
Other comprehensive income before reclassification	1,936	805
Amounts reclassified from accumulated other comprehensive income	(565)	(31)
Net current period other comprehensive gain	1,371	774
Balances	1,581	2,734
Defined Benefit and Other Benefit Plans [Member]
Changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward]
Balances	(11,152)	(10,745)
Other comprehensive income before reclassification	0	0
Amounts reclassified from accumulated other comprehensive income	233	224
Net current period other comprehensive gain	233	224
Balances	$ (10,919)	$ (10,521)

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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