Fair Value Measurement - Assets and Liabilities Measured at Fair Value (Detail) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities available for sale	$ 646,145	$ 648,067
Equity securities	2,392	2,421
Swap asset	6,070	6,330
(Level 2) [Member] \| Assets Measured at Fair Value on a Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities available for sale	646,145	648,067
Equity securities	2,392	2,421
(Level 2) [Member] \| Assets Measured at Fair Value on a Recurring Basis [Member] \| Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Swap asset	2,845	5,308
Swap liability	8,915	11,638
(Level 2) [Member] \| Assets Measured at Fair Value on a Recurring Basis [Member] \| U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities available for sale	64,984	97,387
(Level 2) [Member] \| Assets Measured at Fair Value on a Recurring Basis [Member] \| Obligations of States and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities available for sale	320,214	325,119
(Level 2) [Member] \| Assets Measured at Fair Value on a Recurring Basis [Member] \| Mortgage-backed Securities in Government Sponsored Entities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities available for sale	260,947	225,561
(Level 3) [Member] \| Assets Measured at Fair Value on a Nonrecurring Basis [Member] \| Collateral-Dependent Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	$ 19,793	$ 19,177

Fair value portion of asset recognized for present right to economic benefit.

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