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Schedule of Reported Financial Assets and Liabilities (Detail) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Sep. 28, 2025	Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	$ 427,685	$ 725,452
Liabilities	1,129	1,324
Other Current Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities	1,129	1,324
Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	272,700	553,354
Long-term marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	129,658	124,121
Marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	25,017	46,312
Prepayments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	310	1,665
Quoted Prices in Active Markets for Identical Instruments (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	342,220	607,576
Liabilities	0	0
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Other Current Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities	0	0
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	272,700	544,213
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Long-term marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	69,520	63,363
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	0	0
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Prepayments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	0	0
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	85,465	117,876
Liabilities	1,129	1,324
Significant Other Observable Inputs (Level 2) | Other Current Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities	1,129	1,324
Significant Other Observable Inputs (Level 2) | Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	0	9,141
Significant Other Observable Inputs (Level 2) | Long-term marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	60,138	60,758
Significant Other Observable Inputs (Level 2) | Marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	25,017	46,312
Significant Other Observable Inputs (Level 2) | Prepayments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	310	1,665
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	0	0
Liabilities	0	0
Significant Unobservable Inputs (Level 3) | Other Current Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities	0	0
Significant Unobservable Inputs (Level 3) | Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	0	0
Significant Unobservable Inputs (Level 3) | Long-term marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	0	0
Significant Unobservable Inputs (Level 3) | Marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	0	0
Significant Unobservable Inputs (Level 3) | Prepayments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	$ 0	$ 0

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