Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 36,585	$ 29,285	$ 70,554	$ 57,479
Unrealized (losses) gains on securities available for sale:
Unrealized holding (losses) gains arising during the period, pretax	(109,623)	4,326	(291,418)	(19,909)
Tax benefit (expense)	25,192	(994)	66,968	4,575
Postretirement Plans:
Amortization of unrecognized net actuarial loss	44	205	88	376
Tax benefit	(10)	(77)	(20)	(117)
Other comprehensive (loss) income	(84,397)	3,460	(224,382)	(15,075)
Comprehensive (loss) income	$ (47,812)	$ 32,745	$ (153,828)	$ 42,404

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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