Fair Value Measurements - Quantitative Information about the Inputs and Valuation Methodologies Used for Fair Value Measurements (Details) - Fair Value Measurements Recurring - Earn Out Liability $ in Thousands	Sep. 29, 2018 USD ($)	Dec. 30, 2017 USD ($)
Quantitative information about the inputs and valuation methodologies used for fair value measurements
Liabilities, Fair Value Measurements	$ 364	$ 572
Level 3
Quantitative information about the inputs and valuation methodologies used for fair value measurements
Liabilities, Fair Value Measurements	$ 364	$ 572
Valuation Technique, Earn-out liability	us-gaap:ValuationTechniqueDiscountedCashFlowMember	us-gaap:ValuationTechniqueDiscountedCashFlowMember
Level 3 | Discounted Cash Flow | Weighted Average
Quantitative information about the inputs and valuation methodologies used for fair value measurements
Weighted Average, Projected royalties	$ 1,314	$ 1,622
Discount Rate | Level 3 | Weighted Average
Quantitative information about the inputs and valuation methodologies used for fair value measurements
Weighted Average, Discount rate	10.35	10.90
Discount Rate | Level 3 | Minimum
Quantitative information about the inputs and valuation methodologies used for fair value measurements
Weighted Average, Discount rate	10.20	10.90
Discount Rate | Level 3 | Maximum
Quantitative information about the inputs and valuation methodologies used for fair value measurements
Weighted Average, Discount rate	27.00	27.00