Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 46,567	$ 40,063	$ 119,792	$ 138,838
Securities available for sale:
Unrealized holding losses on securities	(63,579)	(9,250)	(220,999)	(20,491)
Reclassification adjustment for gains realized in net income	0	(570)	0	(1,582)
Amortization of unrealized holding gains on securities transferred to the held to maturity category	1,207	0	969	0
Total securities available for sale	(62,372)	(9,820)	(220,030)	(22,073)
Derivative instruments:
Unrealized holding gains on derivative instruments	1,687	1,215	14,328	7,551
Total derivative instruments	1,687	1,215	14,328	7,551
Defined benefit pension and post-retirement benefit plans:
Amortization of net actuarial loss recognized in net periodic pension cost	31	49	93	148
Total defined benefit pension and post-retirement benefit plans	31	49	93	148
Other comprehensive loss, net of tax	(60,654)	(8,556)	(205,609)	(14,374)
Comprehensive (loss) income	$ (14,087)	$ 31,507	$ (85,817)	$ 124,464