Premises and Equipment - Components of Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property Plant And Equipment [Line Items]
Cost	$ 527,061	$ 529,494
Accumulated Depreciation and Amortization	(332,206)	(322,717)
Net Book Value	194,855	206,777
Premises
Property Plant And Equipment [Line Items]
Cost	380,837	380,978
Accumulated Depreciation and Amortization	(240,471)	(233,744)
Net Book Value	140,366	147,234
Equipment
Property Plant And Equipment [Line Items]
Cost	139,631	141,923
Accumulated Depreciation and Amortization	(87,230)	(84,540)
Net Book Value	52,401	57,383
Finance leases
Property Plant And Equipment [Line Items]
Cost	6,593	6,593
Accumulated Depreciation and Amortization	(4,505)	(4,433)
Net Book Value	$ 2,088	$ 2,160