Fair Value Measurement - Summary of Fair Values and Gross Unrealized Losses of Available for Sale Securities (Detail) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 months, Recorded Basis	$ 3,064	$ 829
Less than 12 months, Gross Unrealized Losses	(124)	(1)
12 months or longer, Recorded Basis	181,595	209,323
12 months or longer, Gross Unrealized Losses	(15,971)	(15,981)
Total, Recorded Basis	184,659	210,152
Total, Gross Unrealized Losses	(16,095)	(15,982)
Investments [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 months, Recorded Basis	906
Less than 12 months, Gross Unrealized Losses	(104)
12 months or longer, Recorded Basis	39,746	55,738
12 months or longer, Gross Unrealized Losses	(3,782)	(4,003)
Total, Recorded Basis	40,652	55,738
Total, Gross Unrealized Losses	(3,886)	(4,003)
Investments [Member] \| Corporate Bonds [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 months, Recorded Basis	906
Less than 12 months, Gross Unrealized Losses	(104)
12 months or longer, Recorded Basis	17,099	26,394
12 months or longer, Gross Unrealized Losses	(1,003)	(1,238)
Total, Recorded Basis	18,005	26,394
Total, Gross Unrealized Losses	(1,107)	(1,238)
Investments [Member] \| U.S. Treasuries [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
12 months or longer, Recorded Basis	13,630	13,627
12 months or longer, Gross Unrealized Losses	(631)	(634)
Total, Recorded Basis	13,630	13,627
Total, Gross Unrealized Losses	(631)	(634)
Investments [Member] \| Mortgage-Backed Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
12 months or longer, Recorded Basis	8,683	9,148
12 months or longer, Gross Unrealized Losses	(2,102)	(2,026)
Total, Recorded Basis	8,683	9,148
Total, Gross Unrealized Losses	(2,102)	(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		5,267
12 months or longer, Gross Unrealized Losses		(42)
Total, Recorded Basis		5,267
Total, Gross Unrealized Losses		(42)
Investments [Member] \| Asset-Backed Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
12 months or longer, Recorded Basis	334	1,302
12 months or longer, Gross Unrealized Losses	(46)	(63)
Total, Recorded Basis	334	1,302
Total, Gross Unrealized Losses	(46)	(63)
Restricted Investments [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 months, Recorded Basis	2,158	829
Less than 12 months, Gross Unrealized Losses	(20)	(1)
12 months or longer, Recorded Basis	141,849	153,585
12 months or longer, Gross Unrealized Losses	(12,189)	(11,978)
Total, Recorded Basis	144,007	154,414
Total, Gross Unrealized Losses	(12,209)	(11,979)
Restricted Investments [Member] \| Corporate Bonds [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 months, Recorded Basis	373	100
12 months or longer, Recorded Basis	66,608	73,745
12 months or longer, Gross Unrealized Losses	(3,734)	(3,876)
Total, Recorded Basis	66,981	73,845
Total, Gross Unrealized Losses	(3,734)	(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	721	729
Less than 12 months, Gross Unrealized Losses	(12)	(1)
12 months or longer, Recorded Basis	47,040	47,313
12 months or longer, Gross Unrealized Losses	(3,989)	(3,766)
Total, Recorded Basis	47,761	48,042
Total, Gross Unrealized Losses	(4,001)	(3,767)
Restricted Investments [Member] \| Mortgage-Backed Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 months, Recorded Basis	915
Less than 12 months, Gross Unrealized Losses	(8)
12 months or longer, Recorded Basis	24,431	26,916
12 months or longer, Gross Unrealized Losses	(4,131)	(4,000)
Total, Recorded Basis	25,346	26,916
Total, Gross Unrealized Losses	(4,139)	(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	3,770	5,611
12 months or longer, Gross Unrealized Losses	(335)	(336)
Total, Recorded Basis	3,770	5,611
Total, Gross Unrealized Losses	(335)	$ (336)
Restricted Investments [Member] \| Asset-Backed Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 months, Recorded Basis	149
Total, Recorded Basis	$ 149

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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