v3.26.1
Fair Value Measurement - Assets and Liabilities Measured at Fair Value (Detail) - USD ($)
$ in Thousands
Mar. 31, 2026
Dec. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total securities available for sale [1] $ 679,737 $ 681,908
Equity securities 2,725 2,692
Swap asset 3,360 2,180
(Level 1) [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 32,475 33,902
(Level 1) [Member] | Assets Measured at Fair Value on a Recurring Basis [Member] | U.S. Treasury securities [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total securities available for sale 32,475 33,902
(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 647,262 648,006
Equity securities 2,725 2,692
(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 2,716 3,494
Swap liability 5,853 5,748
(Level 2) [Member] | Assets Measured at Fair Value on a Recurring Basis [Member] | 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 25,079 27,115
(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 317,366 324,798
(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 304,817 296,093
(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 $ 11,640 $ 13,140
[1] Excludes accrued interest receivable on securities of $3,815 and $4,371 at March 31, 2026 and December 31, 2025, respectively, that is recorded in Accrued interest receivable on the Consolidated Balance Sheets.