CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) [Abstract]
Net Income	$ 4,705	$ 11,782	$ 29,241	$ 38,848
Other comprehensive income (loss):
Change in unrealized holding gain (loss) on securities available-for-sale	1,996	(2,774)	10,944	(7,011)
Change in pension and other postretirement obligations	237	287	966	728
Change in unrealized gain (loss) on derivatives	(2,323)	754	(11,684)	3,330
Other comprehensive income (loss) before income taxes	(90)	(1,733)	226	(2,953)
Deferred tax expense (benefit)	(70)	(577)	34	(981)
Other comprehensive income (loss), net of tax	(20)	(1,156)	192	(1,972)
Total comprehensive income	$ 4,685	$ 10,626	$ 29,433	$ 36,876