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Stock-Based Compensation - Schedule of Weighted Average Assumptions Used for Calculation of Fair Value of Stock Options Granted (Details) - $ / shares
12 Months Ended
Jan. 31, 2018
Jan. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]    
Expected volatility 46.16% 47.81%
Expected life in years 6 years 6 years
Risk-free interest rates 1.93% 1.42%
Dividend rate 1.51% 1.01%
Weighted average fair value per option at date of grant $ 9.15 $ 11.17