Fair Value of Financial Instruments - Summary of financial instruments (Details) - USD ($) $ in Thousands	Apr. 03, 2021	Jan. 02, 2021
Financial assets and liabilities measured at fair value on a recurring basis
Short-term investments	$ 367,708	$ 521,963
Recurring
Financial assets and liabilities measured at fair value on a recurring basis
Cash equivalents	68,481	95,520
Short-term investments	367,708	521,963
Other assets, net	5,262	5,340
Total assets at fair value	441,451	622,823
Recurring | Money market funds
Financial assets and liabilities measured at fair value on a recurring basis
Cash equivalents	67,279	75,606
Recurring | Corporate debt securities
Financial assets and liabilities measured at fair value on a recurring basis
Cash equivalents	1,202	14,995
Short-term investments	282,358	379,390
Recurring | Government debt securities
Financial assets and liabilities measured at fair value on a recurring basis
Cash equivalents		4,919
Short-term investments	85,350	142,573
Recurring | Auction rate securities
Financial assets and liabilities measured at fair value on a recurring basis
Other assets, net	5,262	5,340
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Financial assets and liabilities measured at fair value on a recurring basis
Cash equivalents	67,279	77,961
Short-term investments	5,226	38,461
Total assets at fair value	72,505	116,422
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Money market funds
Financial assets and liabilities measured at fair value on a recurring basis
Cash equivalents	67,279	75,606
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Government debt securities
Financial assets and liabilities measured at fair value on a recurring basis
Cash equivalents		2,355
Short-term investments	5,226	38,461
Recurring | Significant Other Observable Inputs (Level 2)
Financial assets and liabilities measured at fair value on a recurring basis
Cash equivalents	1,202	17,559
Short-term investments	362,482	483,502
Total assets at fair value	363,684	501,061
Recurring | Significant Other Observable Inputs (Level 2) | Corporate debt securities
Financial assets and liabilities measured at fair value on a recurring basis
Cash equivalents	1,202	14,995
Short-term investments	282,358	379,390
Recurring | Significant Other Observable Inputs (Level 2) | Government debt securities
Financial assets and liabilities measured at fair value on a recurring basis
Cash equivalents		2,564
Short-term investments	80,124	104,112
Recurring | Significant Unobservable Inputs (Level 3)
Financial assets and liabilities measured at fair value on a recurring basis
Other assets, net	5,262	5,340
Total assets at fair value	5,262	5,340
Recurring | Significant Unobservable Inputs (Level 3) | Auction rate securities
Financial assets and liabilities measured at fair value on a recurring basis
Other assets, net	$ 5,262	$ 5,340