Components of Net Realized Investment Gains (Losses) (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Schedule Of Available For Sale Securities [Line Items]
Total net realized investment gains (losses)	$ (2,243)	$ 136
Equity securities, Gross realized gains	5	123
Equity securities, Gross realized losses	(2,269)	0
Net realized gains (losses)	(2,264)	123
Fixed Income Securities
Schedule Of Available For Sale Securities [Line Items]
Gross realized gains	24	14
Gross realized losses	(3)	(1)
Total net realized investment gains (losses)	$ 21	$ 13

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details