Fair Value Measurement - Summary of Fair Values and Gross Unrealized Losses of Available for Sale Securities (Detail) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 months, Recorded Basis	$ 1,611	$ 829
Less than 12 months, Gross Unrealized Losses	(132)	(1)
12 months or longer, Recorded Basis	207,793	209,323
12 months or longer, Gross Unrealized Losses	(16,212)	(15,981)
Total, Recorded Basis	209,404	210,152
Total, Gross Unrealized Losses	(16,344)	(15,982)
Investments [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 months, Recorded Basis	885
Less than 12 months, Gross Unrealized Losses	(126)
12 months or longer, Recorded Basis	54,207	55,738
12 months or longer, Gross Unrealized Losses	(3,950)	(4,003)
Total, Recorded Basis	55,092	55,738
Total, Gross Unrealized Losses	(4,076)	(4,003)
Investments [Member] \| Corporate Bonds [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 months, Recorded Basis	885
Less than 12 months, Gross Unrealized Losses	(126)
12 months or longer, Recorded Basis	18,929	26,394
12 months or longer, Gross Unrealized Losses	(1,129)	(1,238)
Total, Recorded Basis	19,814	26,394
Total, Gross Unrealized Losses	(1,255)	(1,238)
Investments [Member] \| U.S. Treasuries [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
12 months or longer, Recorded Basis	13,621	13,627
12 months or longer, Gross Unrealized Losses	(639)	(634)
Total, Recorded Basis	13,621	13,627
Total, Gross Unrealized Losses	(639)	(634)
Investments [Member] \| Mortgage-Backed Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
12 months or longer, Recorded Basis	8,929	9,148
12 months or longer, Gross Unrealized Losses	(2,075)	(2,026)
Total, Recorded Basis	8,929	9,148
Total, Gross Unrealized Losses	(2,075)	(2,026)
Investments [Member] \| U.S. Government Agency Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
12 months or longer, Recorded Basis	5,245	5,267
12 months or longer, Gross Unrealized Losses	(42)	(42)
Total, Recorded Basis	5,245	5,267
Total, Gross Unrealized Losses	(42)	(42)
Investments [Member] \| Asset-Backed Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
12 months or longer, Recorded Basis	7,483	1,302
12 months or longer, Gross Unrealized Losses	(65)	(63)
Total, Recorded Basis	7,483	1,302
Total, Gross Unrealized Losses	(65)	(63)
Restricted Investments [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 months, Recorded Basis	726	829
Less than 12 months, Gross Unrealized Losses	(6)	(1)
12 months or longer, Recorded Basis	153,586	153,585
12 months or longer, Gross Unrealized Losses	(12,262)	(11,978)
Total, Recorded Basis	154,312	154,414
Total, Gross Unrealized Losses	(12,268)	(11,979)
Restricted Investments [Member] \| Corporate Bonds [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 months, Recorded Basis		100
12 months or longer, Recorded Basis	73,525	73,745
12 months or longer, Gross Unrealized Losses	(3,956)	(3,876)
Total, Recorded Basis	73,525	73,845
Total, Gross Unrealized Losses	(3,956)	(3,876)
Restricted Investments [Member] \| U.S. Treasuries [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 months, Recorded Basis	726	729
Less than 12 months, Gross Unrealized Losses	(6)	(1)
12 months or longer, Recorded Basis	47,168	47,313
12 months or longer, Gross Unrealized Losses	(3,885)	(3,766)
Total, Recorded Basis	47,894	48,042
Total, Gross Unrealized Losses	(3,891)	(3,767)
Restricted Investments [Member] \| Mortgage-Backed Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
12 months or longer, Recorded Basis	27,297	26,916
12 months or longer, Gross Unrealized Losses	(4,077)	(4,000)
Total, Recorded Basis	27,297	26,916
Total, Gross Unrealized Losses	(4,077)	(4,000)
Restricted Investments [Member] \| U.S. Government Agency Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
12 months or longer, Recorded Basis	5,596	5,611
12 months or longer, Gross Unrealized Losses	(344)	(336)
Total, Recorded Basis	5,596	5,611
Total, Gross Unrealized Losses	$ (344)	$ (336)

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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