Warrants (Details) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 28, 2019 USD ($)	Jun. 29, 2018 USD ($)	Jun. 28, 2019 USD ($)	Jun. 29, 2018 USD ($)	Jul. 09, 2019 shares	Dec. 31, 2018 Measurement_Input	Jul. 31, 2018 shares	Sep. 26, 2016 $ / shares shares
Class of Warrant or Right [Line Items]
Warrants, Exercise Price of Warrants | $ / shares								$ 4.76
Reduction to net revenues - amortization of the Warrant | $			$ 48	$ 395
Comcast Product Supply Agreement [Member]
Class of Warrant or Right [Line Items]
Right to purchase shares vested								781,617
Comcast Milestones Achievement [Member]
Class of Warrant or Right [Line Items]
Right to purchase shares vested							1,172,425
Measurement Input, Expected Dividend Rate [Member] | Comcast Warrant Vesting Tranche July 31, 2018 [Member]
Class of Warrant or Right [Line Items]
Warrants and Rights Outstanding, Measurement Input | Measurement_Input						0
Maximum [Member] | Comcast Warrant Expires September 26, 2023 [Member]
Class of Warrant or Right [Line Items]
Warrant Grant to Purchase Shares of Common Stock								7,816,162
Revenue from Contract with Customer [Member]
Class of Warrant or Right [Line Items]
Reduction to net revenues - amortization of the Warrant | $	$ 23	$ 300	$ 48	$ 395
Subsequent Event [Member] | Comcast’s Election for Enterprise License Pricing [Member]
Class of Warrant or Right [Line Items]
Right to purchase shares vested					781,617