Investments - Summary of Sales of Available-for-sale Fixed-Maturity Securities (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Schedule of Available-for-sale Securities [Line Items]
Proceeds	$ 6,030	$ 11,060
Fixed-Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds	6,030	11,060
Gross Realized Gains	12	0
Gross Realized Losses	$ (44)	$ (738)

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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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details