Investments - Investment Income (Loss) Summarized (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Schedule Of Investments [Line Items]
Net income from limited partnership interests			$ 85	$ 542
Real estate investments	$ 3,783	$ 270	5,276	9,563
Net Investment Income	16,881	8,794	30,948	26,509
Available-for-Sale-Fixed-Maturity Securities [Member]
Schedule Of Investments [Line Items]
Investment income	6,020	5,120	10,848	9,155
Equity Securities [Member]
Schedule Of Investments [Line Items]
Investment income	511	378	952	674
Investment Expense [Member]
Schedule Of Investments [Line Items]
Investment expense	(141)	(125)	(220)	(254)
Limited Partnership Investment [Member]
Schedule Of Investments [Line Items]
Net income from limited partnership interests	(110)	(11)	85	542
Cash and Cash Equivalents [Member]
Schedule Of Investments [Line Items]
Investment income	$ 6,818	$ 3,162	$ 14,007	$ 6,829