Premises and Equipment, Net and Other Assets - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Noncash construction in progress for retainage payable	$ 1,000,000.0
Cash surrender value of life insurance policies	$ 81,400,000	$ 80,700,000
Percentage of equity investment	50.00%
Low income housing tax credit investments	$ 20,100,000	18,100,000
Tax credits and other tax benefits recognized from LIHTC investments	6,500,000	5,600,000	$ 5,400,000
Equity securities	10,600,000	10,100,000
Other assets in equity interest	16,400,000	11,100,000
Amortization expense resulting from LIHTC investments	5,500,000	4,600,000	4,500,000
Unfunded commitment on investments	$ 17,000,000.0
Percentage of qualified investment	39.00%
Period of qualified investments taken	7 years
New market tax credit investments	$ 15,200,000	18,500,000
Tax credits and other tax benefits recognized from NMTC investments	4,000,000.0	4,000,000.0	4,500,000
Amortization expense resulting from NMTC investments	3,300,000	$ 3,300,000	$ 3,700,000
Unfunded commitment on NMTC investments	$ 0