Net Income (Loss) per Share - Antidilutive Securities (Details) - 2015 Employee Stock Purchase Plan - shares shares in Thousands	3 Months Ended
	Apr. 04, 2020	Mar. 30, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	37,598	41,293
Stock options to purchase common stock | Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	12,645	15,774
RSUs | Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	24,723	24,002
Warrant | Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	230	230
Diluted impact of Employee Stock Purchase Plan | Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	0	1,287