Fair Value Measurements - Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Jul. 09, 2022	Jun. 30, 2022	Dec. 31, 2021
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Accrued litigation payable		$ 15,656	$ 7,118
Private Placement | Subsequent Event
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Shares to be issued in private placement (in shares)	2,229,296
Value of shares to be issued in private placement	$ 10,700
Fair Value, Measurements, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		83,852	317,938
Accrued litigation payable		10,656
Fair Value, Measurements, Recurring | Current Assets | Equity securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		6,246	6,698
Fair Value, Measurements, Recurring | Current Assets | Foreign bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value			115
Fair Value, Measurements, Recurring | Current Assets | Mutual funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		37	38
Fair Value, Measurements, Recurring | Current Assets | Cash and cash equivalents
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		61,900	181,101
Fair Value, Measurements, Recurring | Current Assets | Cash and cash equivalents | Corporate debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value			54,200
Fair Value, Measurements, Recurring | Current Assets | Cash and cash equivalents | Government-sponsored securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value			75,000
Fair Value, Measurements, Recurring | Current Assets | Cash and cash equivalents | Commercial paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value			500
Fair Value, Measurements, Recurring | Current Assets | Corporate debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		14,755	129,164
Fair Value, Measurements, Recurring | Noncurrent Assets | Foreign bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		914	822
Fair Value, Measurements, Recurring | Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		68,183	59,094
Accrued litigation payable		10,656
Fair Value, Measurements, Recurring | Level 1 | Current Assets | Equity securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		6,246	6,698
Fair Value, Measurements, Recurring | Level 1 | Current Assets | Foreign bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value			115
Fair Value, Measurements, Recurring | Level 1 | Current Assets | Mutual funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		37	38
Fair Value, Measurements, Recurring | Level 1 | Current Assets | Cash and cash equivalents
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		61,900	51,421
Fair Value, Measurements, Recurring | Level 1 | Current Assets | Corporate debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		0	0
Fair Value, Measurements, Recurring | Level 1 | Noncurrent Assets | Foreign bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		0	822
Fair Value, Measurements, Recurring | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		15,669	258,844
Accrued litigation payable		0
Fair Value, Measurements, Recurring | Level 2 | Current Assets | Equity securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		0	0
Fair Value, Measurements, Recurring | Level 2 | Current Assets | Foreign bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value			0
Fair Value, Measurements, Recurring | Level 2 | Current Assets | Mutual funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		0	0
Fair Value, Measurements, Recurring | Level 2 | Current Assets | Cash and cash equivalents
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		0	129,680
Fair Value, Measurements, Recurring | Level 2 | Current Assets | Corporate debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		14,755	129,164
Fair Value, Measurements, Recurring | Level 2 | Noncurrent Assets | Foreign bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		914	0
Fair Value, Measurements, Recurring | Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		0	0
Accrued litigation payable		0
Fair Value, Measurements, Recurring | Level 3 | Current Assets | Equity securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		0	0
Fair Value, Measurements, Recurring | Level 3 | Current Assets | Foreign bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value			0
Fair Value, Measurements, Recurring | Level 3 | Current Assets | Mutual funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		0	0
Fair Value, Measurements, Recurring | Level 3 | Current Assets | Cash and cash equivalents
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		0	0
Fair Value, Measurements, Recurring | Level 3 | Current Assets | Corporate debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		0	0
Fair Value, Measurements, Recurring | Level 3 | Noncurrent Assets | Foreign bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		$ 0	$ 0