ACCUMULATED OTHER COMPREHENSIVE (LOSS) INCOME (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
ACCUMULATED OTHER COMPREHENSIVE (LOSS) INCOME
Unrealized holding (losses) gains on available for sale securities	$ (4,231)	$ 2,595	$ (12,818)	$ 4,211
Reclassification adjustment for losses realized in income	7,921	0	7,921	0
Income tax effect	(1,074)	(1,062)	1,425	(1,668)
Net change in unrealized gains (losses) on available for sale securities	2,616	1,533	(3,472)	2,543
Reclassification adjustment for amortization realized in income	95	113	190	227
Income tax effect	(27)	(47)	(55)	(64)
Net change in post-retirement obligation	68	66	135	163
Change in fair value of derivatives used for cash flow hedges	1,020	(1,385)	3,847	(1,360)
Reclassification adjustment for (gains) losses realized in income	(344)	459	(279)	734
Income tax effect	(197)	379	(1,038)	253
Net change in unrealized gains (losses) on cash flow hedges	479	(547)	2,530	(373)
Other comprehensive income (loss)	$ 3,163	$ 1,052	$ (807)	$ 2,333

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