ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Changes in Accumulated Other Comprehensive Income (Loss) By Component (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
AOCI Attributable to Parent, Net of Tax
Balance	$ 148,054	$ 125,821	$ 119,611
Transfer of securities from available-for-sale to held-to-maturity			8
Accretion of unrealized losses of securities transferred from available-for-sale to held-to-maturity recognized in other comprehensive income	889	519	472
Other comprehensive income (loss)	241	(975)	672
Balance	156,503	148,054	125,821
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax
Balance	(6,023)	(5,048)	(5,720)
Other comprehensive income before reclassifications	(933)	(1,739)	180
Accretion of unrealized losses of securities transferred from available-for-sale to held-to-maturity recognized in other comprehensive income	889	519	472
Reclassification adjustments for (gains) losses reclassified into income	285	245	20
Other comprehensive income (loss)	241	(975)	672
Balance	(5,782)	(6,023)	(5,048)
Accumulated Other Comprehensive Income (Loss) | Available-For-Sale
AOCI Attributable to Parent, Net of Tax
Balance	166
Other comprehensive income before reclassifications	(717)
Other comprehensive income (loss)	(717)
Balance	(551)	166
Unrealized Gains (Losses) on Securities | Available-For-Sale
AOCI Attributable to Parent, Net of Tax
Balance	166	1,474	(162)
Other comprehensive income before reclassifications		(1,308)	1,713
Transfer of securities from available-for-sale to held-to-maturity			(8)
Reclassification adjustments for (gains) losses reclassified into income			(69)
Other comprehensive income (loss)		(1,308)	1,636
Balance		166	1,474
Unrealized Gains (Losses) on Securities | Transferred From Available-For-Sale to Held-To-Maturity
AOCI Attributable to Parent, Net of Tax
Balance	(2,297)	(2,816)	(3,296)
Transfer of securities from available-for-sale to held-to-maturity			8
Accretion of unrealized losses of securities transferred from available-for-sale to held-to-maturity recognized in other comprehensive income	889	519	472
Other comprehensive income (loss)	889	519	480
Balance	(1,408)	(2,297)	(2,816)
Pension Plan.
AOCI Attributable to Parent, Net of Tax
Balance	(3,737)	(3,395)	(1,790)
Other comprehensive income before reclassifications	(371)	(587)	(1,694)
Reclassification adjustments for (gains) losses reclassified into income	285	245	89
Other comprehensive income (loss)	(86)	(342)	(1,605)
Balance	(3,823)	(3,737)	(3,395)
Interest Rate Swaps
AOCI Attributable to Parent, Net of Tax
Balance	(155)	(311)	(472)
Other comprehensive income before reclassifications	155	156	161
Other comprehensive income (loss)	$ 155	156	161
Balance		$ (155)	$ (311)