Income Taxes - Effective Tax Rates Differed from Statutory Federal Income Tax Rate (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Income taxes computed at the statutory federal tax rate	$ 7,681	$ 10,629	$ 9,878
Add (subtract) tax effect of:
Tax-exempt interest income, net	(1,975)	(1,938)	(1,666)
Low income housing investments	(555)	(620)	(679)
Cash surrender value of BOLI	(471)	(233)	(207)
Other	211	(189)	282
Income tax expense	$ 4,891	$ 7,649	$ 7,608