CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net Income	$ 18,143	$ 10,940	$ 37,883	$ 24,433
Other comprehensive income (loss):
Net change in unrealized gains on available-for-sale securities, net of tax	2,296	7,130	(15,213)	26,060
Net change in unrealized loss on cash flow hedging derivatives, net of tax	(2,364)	52	2,800	(702)
Net gain on postretirement plans, net of tax	171	133	341	266
Other comprehensive income (loss)	103	7,315	(12,072)	25,624
Comprehensive Income	$ 18,246	$ 18,255	$ 25,811	$ 50,057