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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, 2021
Jan. 31, 2020
Jan. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award      
Dividend yield 2.70% 2.30% 2.50%
Expected volatility 30.30% 32.50% 34.50%
Risk-free interest rate 0.40% 1.90% 2.70%
Expected life (in years) 3 years 4 months 24 days 3 years 3 months 18 days 3 years 3 months 18 days