Fair Value Measurement - Assets and Liabilities Measured at Fair Value (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities available for sale	$ 618,272	$ 615,402
Equity securities	2,169	2,190
(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	618,272	615,402
Equity securities	2,169	2,190
(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	12,481	16,579
Swap liability	12,481	16,579
(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	67,658	61,029
(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	338,599	317,248
(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	212,015	237,125
(Level 3) [Member] | Assets Measured at Fair Value on a Nonrecurring Basis [Member] | Mortgage Servicing Rights [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	$ 3,018	$ 2,689