Other Comprehensive Income (Loss) - Schedule of Amounts Reclassified Out of Each Component (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Net (loss) gain on securities transactions	$ (37)	$ 0	$ (84)	$ 317
Tax (expense) benefit	(6,329)	(6,471)	(13,305)	(13,151)
Other operating expense	(13,029)	(10,730)	(25,049)	(21,355)
Total before tax	27,230	29,333	57,510	61,672
Net of tax	20,869	22,831	44,142	48,457
Amount Reclassified from Accumulated Other Comprehensive (Loss) Income | Available-for-sale securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Net (loss) gain on securities transactions	0	0	0
Tax (expense) benefit	0	0	0	(81)
Total before tax				330
Net of tax	0	0	0	249
Amount Reclassified from Accumulated Other Comprehensive (Loss) Income | Net retirement plan actuarial loss
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Other operating expense	(514)	(711)	(1,129)	(1,475)
Amount Reclassified from Accumulated Other Comprehensive (Loss) Income | Net retirement plan prior service cost
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Other operating expense	(53)	(56)	(109)	(111)
Amount Reclassified from Accumulated Other Comprehensive (Loss) Income | Employee benefit plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Tax (expense) benefit	138	188	303	388
Total before tax	(567)	(767)	(1,238)	(1,586)
Net of tax	$ (429)	$ (579)	$ (935)	$ (1,198)