Premises and Equipment - Components of Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Property Plant And Equipment [Line Items]
Cost	$ 529,494	$ 517,918
Accumulated Depreciation and Amortization	(322,717)	(318,525)
Net Book Value	206,777	199,393
Premises
Property Plant And Equipment [Line Items]
Cost	380,978	366,205
Accumulated Depreciation and Amortization	(233,744)	(226,515)
Net Book Value	147,234	139,690
Equipment
Property Plant And Equipment [Line Items]
Cost	141,923	145,120
Accumulated Depreciation and Amortization	(84,540)	(87,649)
Net Book Value	57,383	57,471
Finance leases
Property Plant And Equipment [Line Items]
Cost	6,593	6,593
Accumulated Depreciation and Amortization	(4,433)	(4,361)
Net Book Value	$ 2,160	$ 2,232