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Stock-Based Compensation - Valuation Assumptions for Stock Options (Details)
9 Months Ended
Oct. 28, 2017
Oct. 29, 2016
Employee Service Share Based Compensation Aggregate Disclosures [Abstract]    
Expected volatility 49.90% 39.30%
Risk-free interest rate 1.44% 0.78%
Expected life 3 years 2 years