Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 154,665	$ 22,738	$ 135,098
Other comprehensive (loss) income, net of tax:
Net change in fair value of securities available for sale	(104,258)	23,874	41,158
Net change in fair value of cash flow hedges	(22,454)	14,191	12,636
Net change in other comprehensive income for defined benefit postretirement plans	15,782	60,016	(21,880)
Total other comprehensive (loss) income	(110,930)	98,081	31,914
Total comprehensive income	$ 43,735	$ 120,819	$ 167,012