Fair Value Measurement - Summary of Investments Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	$ 257,690	$ 295,091
Gross Unrealized Gains	14	51
Gross Unrealized Losses	(16,343)	(15,982)
Recorded Basis	241,361	279,160
Cash and Cash Equivalents [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	15,338	44,394
Recorded Basis	15,338	44,394
Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	59,364	66,135
Gross Unrealized Gains	2	22
Gross Unrealized Losses	(4,076)	(4,003)
Recorded Basis	55,290	62,154
Restricted Cash and Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	182,988	184,562
Gross Unrealized Gains	12	29
Gross Unrealized Losses	(12,267)	(11,979)
Recorded Basis	170,733	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	15,338	44,394
Recorded Basis	15,338	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	1,786	486
Recorded Basis	1,786	486
Corporate Bonds [Member] \| Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	21,265	27,827
Gross Unrealized Gains	2	5
Gross Unrealized Losses	(1,255)	(1,238)
Recorded Basis	20,012	26,594
Corporate Bonds [Member] \| Restricted Cash and Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	78,187	79,178
Gross Unrealized Gains	3	8
Gross Unrealized Losses	(3,955)	(3,876)
Recorded Basis	74,235	75,310
U.S. Treasuries [Member] \| Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	14,260	14,261
Gross Unrealized Losses	(639)	(634)
Recorded Basis	13,621	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	51,785	51,809
Gross Unrealized Gains	0
Gross Unrealized Losses	(3,891)	(3,767)
Recorded Basis	47,894	48,042
Mortgage-Backed Securities [Member] \| Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	11,004	11,174
Gross Unrealized Losses	(2,075)	(2,026)
Recorded Basis	8,929	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	31,528	32,560
Gross Unrealized Gains	2	10
Gross Unrealized Losses	(4,077)	(4,000)
Recorded Basis	27,453	28,570
Asset-Backed Securities [Member] \| Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	7,548	7,564
Gross Unrealized Gains		17
Gross Unrealized Losses	(65)	(63)
Recorded Basis	7,483	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	806	980
Gross Unrealized Gains	7	11
Recorded Basis	813	991
Mutual Funds [Member] \| Restricted Cash and Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	12,956	13,602
Recorded Basis	12,956	13,602
U.S. Government Agency Securities [Member] \| Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	5,287	5,309
Gross Unrealized Losses	(42)	(42)
Recorded Basis	5,245	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	5,940	5,947
Gross Unrealized Losses	(344)	(336)
Recorded Basis	$ 5,596	$ 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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