ACCUMULATED OTHER COMPREHENSIVE (LOSS) INCOME - Summary of the Accumulated Other Comprehensive Loss Balances, Net of Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Unrealized (losses) gains on available for sale securities
Balance at the beginning of the period	$ 11,685
Current Period Change	3,918	$ (6,088)
Balance at the end of the period	7,767
Unrealized (losses) gains on pension benefits
Balance at the beginning of the period	(6,365)
Current Period Change	90	67
Balance at the end of the period	(6,275)
Unrealized gains (losses) on cash flow hedges
Balance at the beginning of the period	2,938
Current Period Change	(1,525)	2,051
Balance at the end of the period	1,413
Accumulated other comprehensive (loss) gain, net of income taxes
Balance at the beginning of the period	(15,112)
Current Period Change	2,483	$ (3,970)
Balance at the end of the period	$ (12,629)