Fair Value Measurements - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Proceeds from the sales and maturities of securities available-for-sale	$ 4,300,000	$ 1,000,000
Transfers between Level 1, Level 2 and Level 3 securities	0	0
Realized loss on investments		1,700,000
Net realized gain	1,300,000
Unrealized gain on investments		2,500,000
Net unrealized loss	2,100,000
Credit losses on available-for-sale securities	0	0
Purchases of investments	$ 5,000,000	$ 22,900,000