Premises and Equipment, Net and Other Assets - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Noncash construction in progress for retainage payable	$ 195,000	$ 1,100,000
Cash surrender value of life insurance policies	$ 84,400,000	82,700,000
Percentage of equity investment	50.00%
Low income housing tax credit investments	$ 46,400,000	24,700,000
Tax credits and other tax benefits recognized from LIHTC investments	7,300,000	6,400,000	$ 6,500,000
Equity securities	13,100,000	15,500,000
Other assets in equity interest	0	21,400,000
Amortization expense resulting from LIHTC investments	5,600,000	5,100,000	5,500,000
Unfunded commitment on investments	$ 26,800,000
Percentage of qualified investment	39.00%
Period of qualified investments taken	7 years
New market tax credit investments	$ 12,100,000	11,300,000
Tax credits and other tax benefits recognized from NMTC investments	5,600,000	4,700,000	4,000,000
Amortization expense resulting from NMTC investments	4,600,000	$ 3,900,000	$ 3,300,000
Unfunded commitment on NMTC investments	$ 0