Fair Value Measurement - Summary of Investments Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	$ 220,315	$ 295,091
Gross Unrealized Gains	9	51
Gross Unrealized Losses	(16,095)	(15,982)
Recorded Basis	204,229	279,160
Cash and Cash Equivalents [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	781	44,394
Recorded Basis	781	44,394
Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	44,735	66,135
Gross Unrealized Gains	3	22
Gross Unrealized Losses	(3,886)	(4,003)
Recorded Basis	40,852	62,154
Restricted Cash and Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	174,799	184,562
Gross Unrealized Gains	6	29
Gross Unrealized Losses	(12,209)	(11,979)
Recorded Basis	162,596	172,612
Money Market Funds [Member] \| Cash and Cash Equivalents [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	781	44,394
Recorded Basis	781	44,394
Money Market Funds [Member] \| Restricted Cash and Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	2,443	486
Recorded Basis	2,443	486
Corporate Bonds [Member] \| Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	19,308	27,827
Gross Unrealized Gains	3	5
Gross Unrealized Losses	(1,107)	(1,238)
Recorded Basis	18,204	26,594
Corporate Bonds [Member] \| Restricted Cash and Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	70,899	79,178
Gross Unrealized Gains	1	8
Gross Unrealized Losses	(3,734)	(3,876)
Recorded Basis	67,166	75,310
U.S. Treasuries [Member] \| Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	14,261	14,261
Gross Unrealized Losses	(631)	(634)
Recorded Basis	13,630	13,627
U.S. Treasuries [Member] \| Restricted Cash and Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	51,762	51,809
Gross Unrealized Gains	0
Gross Unrealized Losses	(4,001)	(3,767)
Recorded Basis	47,761	48,042
Mortgage-Backed Securities [Member] \| Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	10,786	11,174
Gross Unrealized Losses	(2,102)	(2,026)
Recorded Basis	8,684	9,148
Mortgage-Backed Securities [Member] \| Restricted Cash and Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	30,109	32,560
Gross Unrealized Gains	3	10
Gross Unrealized Losses	(4,139)	(4,000)
Recorded Basis	25,973	28,570
Asset-Backed Securities [Member] \| Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	380	7,564
Gross Unrealized Gains		17
Gross Unrealized Losses	(46)	(63)
Recorded Basis	334	7,518
Asset-Backed Securities [Member] \| Restricted Cash and Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	662	980
Gross Unrealized Gains	2	11
Recorded Basis	664	991
Mutual Funds [Member] \| Restricted Cash and Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	14,819	13,602
Recorded Basis	14,819	13,602
U.S. Government Agency Securities [Member] \| Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	0	5,309
Gross Unrealized Losses	0	(42)
Recorded Basis	0	5,267
U.S. Government Agency Securities [Member] \| Restricted Cash and Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	4,105	5,947
Gross Unrealized Losses	(335)	(336)
Recorded Basis	$ 3,770	$ 5,611

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in marketable security.

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