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Employee Benefit Plans and Stock-based Compensation - Valuation Assumptions for Stock Options (Details) - Stock Options [Member]
3 Months Ended 6 Months Ended
Jun. 30, 2017
Jul. 01, 2016
Jun. 30, 2017
Jul. 01, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Expected term (years) 4 years 3 months 18 days 4 years 3 months 18 days 4 years 3 months 18 days 4 years 3 months 18 days
Volatility 43.00% 36.00% 43.00% 36.00%
Risk-free interest rate 1.70% 1.10% 1.70% 1.40%
Expected dividends 0.00% 0.00% 0.00% 0.00%