Fair Value Measurement - Assets and Liabilities Measured at Fair Value (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities available for sale	$ 606,249	$ 618,272
Equity securities	2,027	2,169
(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	606,249	618,272
Equity securities	2,027	2,169
(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	14,682	12,481
Swap liability	14,682	12,481
(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	68,042	67,658
(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	333,451	338,599
(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	204,756	212,015
(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	$ 2,999	$ 3,018