Components of Net Realized Investment Gains (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Schedule Of Available For Sale Securities [Line Items]
Total net realized investment gains	$ 136	$ 847
Equity securities, Gross realized gains	123	875
Equity securities, Gross realized losses	0	(3)
Equity securities, Total net realized investment gains	123	872
Fixed Income Securities
Schedule Of Available For Sale Securities [Line Items]
Gross realized gains	14	6
Gross realized losses	(1)	(31)
Total net realized investment gains	$ 13	$ (25)

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