ACCUMULATED OTHER COMPREHENSIVE 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, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 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	$ 1,803	$ (1,327)	3,407	(329)
Balances	143,409	136,520	143,409	136,520
Accumulated Other Comprehensive Income (Loss) [Member]
Changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward]
Balances	(9,338)	(7,787)	(10,942)	(8,785)
Other comprehensive income before reclassification	1,571	(1,394)	3,507	(589)
Amounts reclassified from accumulated other comprehensive income	232	67	(100)	260
Net current period other comprehensive gain	1,803	(1,327)	3,407	(329)
Balances	(7,535)	(9,114)	(7,535)	(9,114)
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	1,581	2,734	210	1,960
Other comprehensive income before reclassification	1,571	(1,394)	3,507	(589)
Amounts reclassified from accumulated other comprehensive income	0	(156)	(565)	(187)
Net current period other comprehensive gain	1,571	(1,550)	2,942	(776)
Balances	3,152	1,184	3,152	1,184
Defined Benefit and Other Benefit Plans [Member]
Changes in accumulated other comprehensive income or loss by component, net of tax [Roll Forward]
Balances	(10,919)	(10,521)	(11,152)	(10,745)
Other comprehensive income before reclassification	0	0	0	0
Amounts reclassified from accumulated other comprehensive income	232	223	465	447
Net current period other comprehensive gain	232	223	465	447
Balances	$ (10,687)	$ (10,298)	$ (10,687)	$ (10,298)