Quarterly report pursuant to Section 13 or 15(d)

Significant Accounting Policies - Schedule of Anti-dilutive Securities Excluded from Computation of Earnings Per Share (Detail)

v3.19.2
Significant Accounting Policies - Schedule of Anti-dilutive Securities Excluded from Computation of Earnings Per Share (Detail) - shares
shares in Thousands
3 Months Ended 6 Months Ended
Jul. 31, 2019
Jul. 31, 2018
Jul. 31, 2019
Jul. 31, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Anti-dilutive potentially outstanding common shares 3,098 3,641 3,323 3,686
Stock Options [Member]        
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Anti-dilutive potentially outstanding common shares 2,596 2,923 2,764 3,014
Restricted Stock Units [Member]        
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Anti-dilutive potentially outstanding common shares 128 193 219 192
Deferred Stock Units [Member]        
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Anti-dilutive potentially outstanding common shares 254 173 229 189
Performance Stock Units (PSUs) [Member]        
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Anti-dilutive potentially outstanding common shares 120 352 111 291