Investments - Schedule of Company's net investment income (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Net Investment Income [Line Items]
Gross investment income, operating	$ 4,246	$ 3,284
Investment expenses	(143)	(36)
Net investment income	4,103	3,248
Fixed maturities, available-for-sale [Member]
Net Investment Income [Line Items]
Gross investment income, operating	2,131	2,091
Cash and cash equivalents [Member]
Net Investment Income [Line Items]
Gross investment income, operating	$ 2,115	$ 1,193

Amount, before investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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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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