ACCUMULATED OTHER COMPREHENSIVE LOSS - Summary of Changes in Accumulated Other Comprehensive Income or Loss by Component (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward]
Beginning balances	$ 182,627	$ 165,029
Other comprehensive income before reclassification	5,696	2,556
Amounts reclassified from accumulated other comprehensive income	21	13
Total other comprehensive income	5,717	2,569
Ending balances	190,447	171,534
Total
Changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward]
Beginning balances	(5,799)	(11,411)
Total other comprehensive income	5,717	2,569
Ending balances	(82)	(8,842)
Unrealized Gains and Losses on Securities Available for Sale
Changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward]
Beginning balances	1,368	(4,646)
Other comprehensive income before reclassification	5,696	2,556
Amounts reclassified from accumulated other comprehensive income	0	0
Total other comprehensive income	5,696	2,556
Ending balances	7,064	(2,090)
Defined Benefit and Other Benefit Plans
Changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward]
Beginning balances	(7,167)	(6,765)
Other comprehensive income before reclassification	0	0
Amounts reclassified from accumulated other comprehensive income	21	13
Total other comprehensive income	21	13
Ending balances	$ (7,146)	$ (6,752)

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

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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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