v3.26.3
Securities - Amortized Cost and Fair Value of Securities with Gross Unrealized Gains and Losses (Detail) - USD ($)
$ in Thousands
Sep. 30, 2026
Dec. 31, 2025
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost $ 479,558 $ 437,120
Gross Unrealized Gains 11 1,378
Gross Unrealized Losses (23,592) (16,426)
Fair Value 455,977 422,072
U.S. Treasury [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 139,923 91,988
Gross Unrealized Gains 0 157
Gross Unrealized Losses (4,406) (2,292)
Fair Value 135,517 89,853
U.S. Government Agencies [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 95,325 136,026
Gross Unrealized Gains 0 116
Gross Unrealized Losses (3,387) (4,181)
Fair Value 91,938 131,961
Corporate Bonds [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 500 0
Gross Unrealized Gains 0 0
Gross Unrealized Losses 0 0
Fair Value 500 0
Mortgage-backed Securities [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 186,711 150,081
Gross Unrealized Gains 0 1,034
Gross Unrealized Losses (12,711) (7,733)
Fair Value 174,000 143,382
State and Local Governments [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 57,099 59,025
Gross Unrealized Gains 11 71
Gross Unrealized Losses (3,088) (2,220)
Fair Value $ 54,022 $ 56,876