Premises and Equipment, Net and Other Assets - Summary of Premises and Equipment by Classification (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property Plant And Equipment [Line Items]
Accumulated depreciation	$ (158,034)	$ (144,381)
Premises and equipment, net	278,594	278,088
Land [Member]
Property Plant And Equipment [Line Items]
Premises and Equipment, gross	49,173	47,856
Buildings [Member]
Property Plant And Equipment [Line Items]
Premises and Equipment, gross	$ 288,391	266,660
Buildings [Member] | Minimum [Member]
Property Plant And Equipment [Line Items]
Estimated Useful Lives	10 years
Buildings [Member] | Maximum [Member]
Property Plant And Equipment [Line Items]
Estimated Useful Lives	40 years
Furniture Fixtures and Equipment [Member]
Property Plant And Equipment [Line Items]
Premises and Equipment, gross	$ 94,851	91,340
Furniture Fixtures and Equipment [Member] | Minimum [Member]
Property Plant And Equipment [Line Items]
Estimated Useful Lives	3 years
Furniture Fixtures and Equipment [Member] | Maximum [Member]
Property Plant And Equipment [Line Items]
Estimated Useful Lives	15 years
Construction in Progress [Member]
Property Plant And Equipment [Line Items]
Premises and Equipment, gross	$ 4,213	$ 16,613