Net Income (Loss) per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
Earnings Per Share [Abstract]
Net income (loss)	$ 13,539	$ 6,974	$ 29,506	$ (19,201)
Shares used in basic Net income (loss) per share (in shares)	132,997	127,816	132,065	125,578
Dilutive effect of stock options, RSUs, ESPP shares, and equity awards with a market condition or performance condition (in shares)	5,897	1,658	5,614	0
Shares used in diluted Net income (loss) per share (in shares)	138,894	129,474	137,679	125,578
Basic Net income (loss) per share (in usd per share)	$ 0.10	$ 0.05	$ 0.22	$ (0.15)
Diluted Net income (loss) per share (in usd per share)	$ 0.10	$ 0.05	$ 0.21	$ (0.15)
Stock options, RSUs, ESPP shares, and equity awards with a market condition or performance condition excluded as they are antidilutive (in shares)	909	2,299	328	8,284