ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Summary of Changes in Accumulated Other Comprehensive Income or Loss by Component (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward]
Beginning balances	$ 190,447	$ 171,534	$ 182,627	$ 165,029
Other comprehensive income before reclassification	2,209	2,891	7,905	5,447
Amounts reclassified from accumulated other comprehensive income	15	0	36	13
Total other comprehensive income	2,224	2,891	7,941	5,460
Ending balances	194,589	178,387	194,589	178,387
Total
Changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward]
Beginning balances	(82)	(8,842)	(5,799)	(11,411)
Total other comprehensive income	2,224	2,891	7,941	5,460
Ending balances	2,142	(5,951)	2,142	(5,951)
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	7,064	(2,090)	1,368	(4,646)
Other comprehensive income before reclassification	2,209	2,891	7,905	5,447
Amounts reclassified from accumulated other comprehensive income	0	(14)	0	(14)
Total other comprehensive income	2,209	2,877	7,905	5,433
Ending balances	9,273	787	9,273	787
Defined Benefit and Other Benefit Plans
Changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward]
Beginning balances	(7,146)	(6,752)	(7,167)	(6,765)
Other comprehensive income before reclassification	0	0	0	0
Amounts reclassified from accumulated other comprehensive income	15	14	36	27
Total other comprehensive income	15	14	36	27
Ending balances	$ (7,131)	$ (6,738)	$ (7,131)	$ (6,738)

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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