Schedule II. Condensed Financial Information of Registrant - Condensed Balance Sheets (Parenthetical) (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Condensed Balance Sheet Statements, Captions [Line Items]
Fixed maturity securities, amortized cost	$ 326,171	$ 338,593
Equity securities, cost	44,046	50,185
Net of Treasury stock	36,929	34,758
Parent Company [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Fixed maturity securities, amortized cost	24,309	19,824
Equity securities, cost	7,108	10,007
Net of Treasury stock	$ 36,929	$ 34,758