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Net Income per Common Share - Additional Information (Detail) - $ / shares
3 Months Ended 9 Months Ended
Oct. 31, 2021
Oct. 31, 2020
Oct. 31, 2021
Oct. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Anti-dilutive common shares 160,000 460,000 173,333  
Anti-dilutive common shares exercise price, minimum $ 38.09 $ 23.74 $ 35.85  
Anti-dilutive common shares exercise price, maximum $ 46.42 $ 46.42 $ 46.42  
Performance Stock Units (PSUs)        
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Anti-dilutive common shares     30,001 271,501