Cash, Cash Equivalents and Short-Term Investments (Detail) - USD ($) $ in Thousands	Apr. 02, 2021	Jan. 01, 2021
Fair Value Measurements [Line Items]
Amortized Cost	$ 214,518	$ 242,518
Gross Unrealized Gains	2	8
Gross Unrealized Losses	0	0
Estimated Fair Value	214,520	242,526
Cash
Fair Value Measurements [Line Items]
Amortized Cost	112,952	146,083
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	112,952	146,083
Money market securities
Fair Value Measurements [Line Items]
Amortized Cost	71,569	51,442
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	71,569	51,442
Total cash equivalents
Fair Value Measurements [Line Items]
Amortized Cost	71,569	51,442
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	71,569	51,442
Total cash and cash equivalents
Fair Value Measurements [Line Items]
Amortized Cost	184,521	197,525
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	184,521	197,525
U.S. Treasury and agency securities
Fair Value Measurements [Line Items]
Amortized Cost	29,997	44,993
Gross Unrealized Gains	2	8
Gross Unrealized Losses	0	0
Estimated Fair Value	29,999	45,001
Total short-term investments
Fair Value Measurements [Line Items]
Amortized Cost	29,997	44,993
Gross Unrealized Gains	2	8
Gross Unrealized Losses	0	0
Estimated Fair Value	$ 29,999	$ 45,001

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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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