v3.26.1
Comprehensive Income and Accumulated Other Comprehensive Loss - Reclassification Out of Accumulated Other Comprehensive Loss (Detail) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]        
Net realized (losses) gains on investments $ (87) $ 3,116 $ (90) $ 3,118
Income before income taxes 18,265 17,455 28,425 28,676
Income tax expense (3,670) (3,500) (5,685) (5,772)
Net income 14,595 13,955 22,740 22,904
Unrealized losses on debt securities, net of tax [Member] | Reclassification Out of Accumulated Other Comprehensive Loss [Member]        
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]        
Net realized (losses) gains on investments (46) (453) (64) (459)
Income before income taxes (46) (453) (64) (459)
Income tax expense 10 95 14 96
Net income $ (36) $ (358) $ (50) $ (363)