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STOCK-BASED COMPENSATION - Summary of Assumptions Used to Estimate Fair Value of Stock Options Granted (Details) - Stock Options Plans
12 Months Ended
Jan. 31, 2018
Jan. 31, 2017
Jan. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award      
Dividend yield 1.70% 1.40% 2.00%
Expected volatility 37.30% 34.60% 34.80%
Risk-free interest rate 1.80% 1.70% 1.30%
Expected life (in years) 3 years 3 months 18 days 4 years 2 months 12 days 4 years 10 months 24 days