v3.26.1
Securities - Gross Unrealized Losses and Fair Value, Aggregated by Investment Category (Detail) - USD ($)
$ in Thousands
Jun. 30, 2026
Dec. 31, 2025
Schedule of Available-for-sale Securities [Line Items]    
12 Months or less, Fair Value $ 95,726 $ 72,020
12 Months or less, Unrealized Loss (746) (537)
More than 12 months, Fair Value 344,926 401,362
More than 12 months, Unrealized Loss (45,823) (46,602)
Total Fair Value 440,652 473,382
Total Unrealized Loss (46,569) (47,139)
U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member]    
Schedule of Available-for-sale Securities [Line Items]    
12 Months or less, Fair Value 7,022 1,168
12 Months or less, Unrealized Loss (87) (2)
More than 12 months, Fair Value 23,903 47,644
More than 12 months, Unrealized Loss (1,118) (1,178)
Total Fair Value 30,925 48,812
Total Unrealized Loss (1,205) (1,180)
Obligations of States and Political Subdivisions [Member]    
Schedule of Available-for-sale Securities [Line Items]    
12 Months or less, Fair Value 50,777 12,606
12 Months or less, Unrealized Loss (201) (45)
More than 12 months, Fair Value 154,103 181,703
More than 12 months, Unrealized Loss (20,151) (21,690)
Total Fair Value 204,880 194,309
Total Unrealized Loss (20,352) (21,735)
Mortgage-backed Securities in Government Sponsored Entities [Member]    
Schedule of Available-for-sale Securities [Line Items]    
12 Months or less, Fair Value 37,927 58,246
12 Months or less, Unrealized Loss (458) (490)
More than 12 months, Fair Value 166,920 172,015
More than 12 months, Unrealized Loss (24,554) (23,734)
Total Fair Value 204,847 230,261
Total Unrealized Loss $ (25,012) $ (24,224)