Fair Value Hierarchy of Available-for-Sale Securities Measured at Fair Value on Recurring Basis (Detail) $ in Thousands	Jul. 04, 2015 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total recurring fair value measurements	$ 51,369
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total recurring fair value measurements	51,369
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	10,566
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	12,505
Fair Value, Measurements, Recurring | Commercial Paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total recurring fair value measurements	4,996
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	17,277
Fair Value, Measurements, Recurring | Municipal bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total recurring fair value measurements	6,025
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	21,070
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	10,566
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	10,504
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	30,299
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | U.S. treasury and agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total recurring fair value measurements	2,001
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	4,996
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	17,277
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Municipal bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total recurring fair value measurements	$ 6,025