Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Oct. 01, 2016	Jul. 02, 2016	Apr. 02, 2016	Jan. 02, 2016	Oct. 03, 2015	Jul. 04, 2015	Apr. 04, 2015	Dec. 31, 2016	Jan. 02, 2016	Jan. 03, 2015
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 118,108	$ 113,225	$ 99,209	$ 96,512	$ 101,194	$ 109,715	$ 106,460	$ 88,597	$ 427,054	$ 405,966	$ 366,127
Gross margin	63,480	67,424	58,426	57,104	54,102	59,849	58,126	47,832
Restructuring charges	951	317	2,568	5,431	3,459	6,818	4,068	4,894	9,267	19,239	17
Net loss	$ (8,164)	$ (12,414)	$ (13,810)	$ (19,711)	$ (45,454)	$ (24,862)	$ (35,570)	$ (53,347)	$ (54,099)	$ (159,233)	$ 48,580
Net loss per share - basic and diluted (in dollars per share)	$ (0.07)	$ (0.10)	$ (0.12)	$ (0.17)	$ (0.38)	$ (0.21)	$ (0.30)	$ (0.46)