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Fair Value Measurement - Summary of Assets Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
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Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | $ 311,991 | $ 298,563
Other [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 9,084 | 26,877
Level 1 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 11,066 | 10,961
Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 291,841 | 260,725
Cash and Cash Equivalents [Member] | Money Market Funds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 8,660 | 26,661
Cash and Cash Equivalents [Member] | Money Market Funds [Member] | Other [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 8,660 | 26,661
Investments [Member] | Corporate Bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 25,982 | 25,592
Investments [Member] | Corporate Bonds [Member] | Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 25,982 | 25,592
Investments [Member] | U.S. Government Agency Securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 12,589 | 12,531
Investments [Member] | U.S. Government Agency Securities [Member] | Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 12,589 | 12,531
Investments [Member] | U.S. Treasuries [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 11,551 | 11,320
Investments [Member] | U.S. Treasuries [Member] | Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 11,551 | 11,320
Investments [Member] | Mortgage-Backed Securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 9,551 | 9,536
Investments [Member] | Mortgage-Backed Securities [Member] | Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 9,551 | 9,536
Investments [Member] | Asset-Backed Securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 7,487 | 7,513
Investments [Member] | Asset-Backed Securities [Member] | Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 7,487 | 7,513
Restricted Cash and Investments [Member] | Money Market Funds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 424 | 216
Restricted Cash and Investments [Member] | Money Market Funds [Member] | Other [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 424 | 216
Restricted Cash and Investments [Member] | Corporate Bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 90,850 | 92,744
Restricted Cash and Investments [Member] | Corporate Bonds [Member] | Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 90,850 | 92,744
Restricted Cash and Investments [Member] | U.S. Government Agency Securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 16,037 | 15,871
Restricted Cash and Investments [Member] | U.S. Government Agency Securities [Member] | Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 16,037 | 15,871
Restricted Cash and Investments [Member] | U.S. Treasuries [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 80,888 | 48,552
Restricted Cash and Investments [Member] | U.S. Treasuries [Member] | Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 80,888 | 48,552
Restricted Cash and Investments [Member] | Mortgage-Backed Securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 34,979 | 35,194
Restricted Cash and Investments [Member] | Mortgage-Backed Securities [Member] | Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 34,979 | 35,194
Restricted Cash and Investments [Member] | Asset-Backed Securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 1,723 | 1,671
Restricted Cash and Investments [Member] | Asset-Backed Securities [Member] | Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 1,723 | 1,671
Restricted Cash and Investments [Member] | Emerging Markets [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 204 | 201
Restricted Cash and Investments [Member] | Emerging Markets [Member] | Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 204 | 201
Restricted Cash and Investments [Member] | Mutual Funds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | 11,066 | 10,961
Restricted Cash and Investments [Member] | Mutual Funds [Member] | Level 1 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total Recorded Basis | $ 11,066 | $ 10,961

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