CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 568,851	$ 473,840	$ 390,606
Unrealized gains and losses on debt securities available for sale
Net (losses) gains arising during the period	(136,981)	(23,613)	27,845
Less reclassification adjustment for net gains included in net income	(23)	(491)	(377)
Total	(137,004)	(24,104)	27,468
Unrealized gains and losses on derivatives (cash flow hedges)
Net gains (losses) on derivatives arising during the period	3,362	127	(2,251)
Less reclassification adjustment for net losses included in net income	203	2,447	2,074
Total	3,565	2,574	(177)
Defined benefit pension and postretirement benefit plans
Net (losses) gains arising during the period	(13,175)	10,306	(3,418)
Amortization of prior service credit	(100)	(96)	(98)
Amortization of actuarial net loss	644	1,106	721
Total	(12,631)	11,316	(2,795)
Other comprehensive (loss) income, net	(146,070)	(10,214)	24,496
Total comprehensive income	$ 422,781	$ 463,626	$ 415,102