Income Taxes - Income Tax Provision Differences from Expected Statutory Provision (Detail)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Expected provision at statutory rate	21.00%	21.00%	21.00%
Difference resulting from:
Tax exempt interest income, net of disallowance	(1.80%)	(1.90%)	(1.70%)
Increase in value of bank owned life insurance assets	(0.80%)	(0.80%)	(0.80%)
Stock-based compensation	0.10%	(0.20%)	(0.20%)
State income taxes, net of federal benefits	1.50%	1.20%	1.10%
Changes in valuation allowance	0.10%	0.20%	0.70%
Federal benefit of state deferred tax asset revaluation	0.00%	0.00%	(0.80%)
Other	0.20%	0.30%	0.30%
Provision for income taxes - effective income tax rate	20.30%	19.80%	19.60%