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Stockholders' Equity and Stock-Based Compensation - Weighted Average Assumptions for Fair Value Stock-Based Awards (Options) (Details)
3 Months Ended
Mar. 30, 2019
Mar. 31, 2018
Weighted average assumptions for fair value estimate of stock-based awards (options)    
Average risk free interest rate 2.15% 2.53%
Expected life (in years) 4 years 6 months 18 days 4 years 6 months 18 days
Average volatility 44.00% 41.00%