Schedule II. Condensed Financial Information of Registrant - Condensed Balance Sheets (Parenthetical) (Detail) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Condensed Balance Sheet Statements, Captions [Line Items]
Fixed maturity securities, amortized cost	$ 317,116	$ 318,975
Equity securities, cost	31,165	36,020
Net of Treasury stock	54,155	42,052
Parent Company [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Fixed maturity securities, amortized cost	997	4,988
Equity securities, cost	0	5,110
Net of Treasury stock	$ 54,155	$ 42,052

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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