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	$ 175,892	$ 83,651	$ 167,596
Securities available for sale:
Unrealized holding (losses) gains on securities	(38,371)	20,717	18,625
Reclassification adjustment for (gains) losses realized in net income	(1,618)	(34)	1,872
Amortization of unrealized holding gains on securities transferred to the held to maturity category	(54)	0	0
Total securities available for sale	(40,043)	20,683	20,497
Derivative instruments:
Unrealized holding gains (losses) on derivative instruments	8,087	688	(2,217)
Reclassification adjustment for (gains) losses realized in net income related to swap termination	(3,486)	1,521	0
Total derivative instruments	4,601	2,209	(2,217)
Defined benefit pension and post-retirement benefit plans:
Net (loss) gain arising during the period	(264)	797	68
Reclassification adjustment for settlement loss related to the VERP realized in net income	0	422	0
New prior service cost	0	(362)	0
Amortization of net actuarial loss recognized in net periodic pension cost	195	193	312
Amortization of prior service cost	0	362	0
Total defined benefit pension and post-retirement benefit plans	(69)	1,412	380
Other comprehensive (loss) income, net of tax	(35,511)	24,304	18,660
Comprehensive income	$ 140,381	$ 107,955	$ 186,256