v3.26.1
Investments - Amortized Cost and Fair Value of Securities Held-to-Maturity (Detail) - USD ($)
$ in Thousands
Mar. 31, 2026
Dec. 31, 2025
Schedule of Held-to-Maturity Securities [Line Items]    
Held-to-Maturity, Amortized Cost $ 5,254 $ 5,248
Held-to-Maturity, Gross Unrecognized Gains 104 161
Held-to-Maturity, Gross Unrecognized Losses (12)  
Held-to-maturity securities 5,346 5,409
Government-Sponsored Residential Mortgage-Backed Securities [Member]    
Schedule of Held-to-Maturity Securities [Line Items]    
Held-to-Maturity, Amortized Cost 3,974 3,967
Held-to-Maturity, Gross Unrecognized Gains 88 131
Held-to-Maturity, Gross Unrecognized Losses (9)  
Held-to-maturity securities 4,053 4,098
State and Political Subdivisions [Member]    
Schedule of Held-to-Maturity Securities [Line Items]    
Held-to-Maturity, Amortized Cost 1,280 1,281
Held-to-Maturity, Gross Unrecognized Gains 16 30
Held-to-Maturity, Gross Unrecognized Losses (3)  
Held-to-maturity securities $ 1,293 $ 1,311