Cash, Cash Equivalents and Investments - Fair Value Hierarchy of Available-for-Sale Securities Measured at Fair Value on Recurring Basis (Detail) $ in Thousands	Jun. 27, 2020 USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total recurring fair value measurements	$ 24,798
Fair Value, Measurements, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total recurring fair value measurements	24,798
Fair Value, Measurements, Recurring | Money market funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total recurring fair value measurements	4,759
Fair Value, Measurements, Recurring | Certificates of deposit
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total recurring fair value measurements	6,209
Fair Value, Measurements, Recurring | Commercial paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total recurring fair value measurements	1,899
Fair Value, Measurements, Recurring | U.S. treasury and agency securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total recurring fair value measurements	5,988
Fair Value, Measurements, Recurring | Corporate bonds and medium-term notes
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total recurring fair value measurements	5,943
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total recurring fair value measurements	10,747
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | Money market funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total recurring fair value measurements	4,759
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | U.S. treasury and agency securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total recurring fair value measurements	5,988
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total recurring fair value measurements	14,051
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Certificates of deposit
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total recurring fair value measurements	6,209
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Commercial paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total recurring fair value measurements	1,899
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Corporate bonds and medium-term notes
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total recurring fair value measurements	$ 5,943