Cash, Cash Equivalents and Short-Term Investments (Detail) - USD ($) $ in Thousands	Oct. 02, 2020	Jan. 03, 2020
Fair Value Measurements [Line Items]
Amortized Cost	$ 207,624	$ 231,277
Gross Unrealized Gains	94	324
Gross Unrealized Losses	0	0
Estimated Fair Value	207,718	231,601
Cash
Fair Value Measurements [Line Items]
Amortized Cost	111,342	135,225
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	111,342	135,225
Money market securities
Fair Value Measurements [Line Items]
Amortized Cost	76,290	41,211
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	76,290	41,211
Total cash equivalents
Fair Value Measurements [Line Items]
Amortized Cost	76,290	41,211
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	76,290	41,211
Total cash and cash equivalents
Fair Value Measurements [Line Items]
Amortized Cost	187,632	176,436
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	187,632	176,436
US Treasury and Government Short-term Debt Securities
Fair Value Measurements [Line Items]
Amortized Cost	19,992	54,841
Gross Unrealized Gains	94	324
Gross Unrealized Losses	0	0
Estimated Fair Value	20,086	55,165
Total short-term investments
Fair Value Measurements [Line Items]
Amortized Cost	19,992	54,841
Gross Unrealized Gains	94	324
Gross Unrealized Losses	0	0
Estimated Fair Value	$ 20,086	$ 55,165

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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