Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Earnings Per Share [Abstract]
Net income (loss)	$ 13,987	$ 13,539	$ 8,559	$ 7,408	$ (7,121)	$ 6,974	$ (20,223)	$ (5,952)	$ 43,493	$ (26,322)	$ (70,562)
Shares used in diluted Net (loss) income per share (in shares)									132,471	126,564	122,677
Dilutive effect of stock options, RSUs, ESPP shares, and equity awards with a market condition or performance condition (in shares)									4,803	0	0
Shares used in diluted Net (loss) income per share (in shares)									137,274	126,564	122,677
Basic Net income (loss) per share (in usd per share)	$ 0.10	$ 0.10	$ 0.06	$ 0.06	$ (0.05)	$ 0.05	$ (0.16)	$ (0.05)	$ 0.33	$ (0.21)	$ (0.58)
Diluted Net income (loss) per share (in usd per share)	$ 0.10	$ 0.10	$ 0.06	$ 0.05	$ (0.05)	$ 0.05	$ (0.16)	$ (0.05)	$ 0.32	$ (0.21)	$ (0.58)
Stock options, RSUs, ESPP shares, and equity awards with a market condition or performance condition excluded as they are antidilutive (in shares)									890	7,567	6,622