CAPITAL RATIOS AND SHAREHOLDERS' EQUITY - Components of OCI (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Net unrealized gain (loss) arising during the period
Before Tax	$ (155)	$ 997			$ 1,775	$ (5,792)
Other comprehensive income
Before Tax	(3,903)	1,653			(5,017)	354
Tax Effect	909	(390)			1,165	(15)
Total other comprehensive (loss) income	(2,994)	1,263	$ (858)	$ (924)	(3,852)	339
Net unrealized gain (loss) on AFS securities
Net unrealized gain (loss) arising during the period
Before Tax	(1,770)	351			(5,348)	9,408
Tax Effect	403	(82)			1,234	(2,143)
Net of Tax	(1,367)	269			(4,114)	7,265
Less: reclassification adjustment for gains (losses) realized in net income
Before Tax	1,930				1,980	1,486
Tax Effect	(458)				(469)	(352)
Net of Tax	1,472	0			1,511	1,134
Other comprehensive income
Before Tax	(3,700)	351			(7,328)	7,922
Tax Effect	861	(82)			1,703	(1,791)
Total other comprehensive (loss) income	(2,839)	269			(5,625)	6,131
Net unrealized gain (loss) on hedging derivatives
Net unrealized gain (loss) arising during the period
Before Tax	(203)	1,302			2,311	(7,568)
Tax Effect	48	(308)			(538)	1,776
Net of Tax	(155)	994			1,773	(5,792)
Less: reclassification adjustment for gains (losses) realized in net income
Net of Tax	0	0			0	0
Other comprehensive income
Before Tax	(203)	1,302			2,311	(7,568)
Tax Effect	48	(308)			(538)	1,776
Total other comprehensive (loss) income	(155)	994			1,773	(5,792)
Net unrealized gain (loss) on post-retirement plans
Net unrealized gain (loss) arising during the period
Net of Tax	0	0			0	0
Less: reclassification adjustment for gains (losses) realized in net income
Net of Tax	0	0			0	0
Other comprehensive income
Total other comprehensive (loss) income	$ 0	$ 0			$ 0	$ 0