v3.8.0.1

Related Party Transactions - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions			3 Months Ended		6 Months Ended	9 Months Ended
		Jun. 29, 2016	Sep. 30, 2017	Sep. 24, 2016	Jul. 01, 2017	Sep. 30, 2017	Jul. 01, 2017	Sep. 24, 2016	Dec. 31, 2016
Related Party Transaction [Line Items]
Related party revenue			$ 457	$ 408		$ 1,281		$ 965
Selling and marketing expenses			3,655	4,698		11,475		11,608
Accounts receivable			221			221			$ 150
Unbilled accounts receivable	[1]		5,462			5,462			5,541
Common Stock
Related Party Transaction [Line Items]
Stock repurchased and retired during period, shares		3.7
Shares repurchased, price per share		$ 8.25
Lock-up provision period		90 days
Affiliated Entity
Related Party Transaction [Line Items]
Related party revenue			500	400		1,300		1,000
Selling and marketing expenses			3,700	$ 4,700		10,300		$ 11,600
Accounts receivable			200			200			100
Unbilled accounts receivable			89			89			286
Deferred revenue									200
Other current liabilities			$ 1,600			$ 1,600			1,100
Accounts payable									$ 100
Director
Related Party Transaction [Line Items]
Selling and marketing expenses							$ 1,400
Related party expenses					$ 1,200
[1] (2) Includes unbilled accounts receivable due from related party of $89 and $286 at September 30, 2017 and December 31, 2016, respectively (Note 13)

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