Investments - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Schedule of Investments [Line Items]
Purchase an available-for-sale debt with credit deterioration	$ 0	$ 0	$ 0
Available-for-sale debt securities	0	$ 9,253,000
Other investments	$ 0
Investment [Member] | Issuer Concentration [Member] | Market Value of Total Investment Portfolio [Member]
Schedule of Investments [Line Items]
Investment concentration risk percentage	5.00%