Premises and Equipment - Schedule of Premises and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	$ 305,838	$ 301,923
Less accumulated depreciation and amortization	191,555	185,815
Total premises and equipment	114,283	116,108
Land	14,814	14,471
Buildings and Improvements, Gross	77,702	75,063
Operating Lease, Right-of-Use Asset	53,654	56,097
Leasehold Improvements, Gross	42,220	40,765
Furniture and Fixtures, Gross	73,975	72,538
Capitalized Computer Software, Gross	$ 43,473	$ 42,989
Minimum [Member] | Buildings and improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	10 years
Minimum [Member] | Property Subject to Operating Lease [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	1 year
Minimum [Member] | Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	5 years
Minimum [Member] | Furniture and equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	3 years
Minimum [Member] | Software [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	3 years
Maximum [Member] | Buildings and improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	50 years
Maximum [Member] | Property Subject to Operating Lease [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	25 years
Maximum [Member] | Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	40 years
Maximum [Member] | Furniture and equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	7 years
Maximum [Member] | Software [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	7 years