Quarterly report pursuant to Section 13 or 15(d)

Net Loss Per Share - Schedule of Anti-dilutive Securities Excluded from Computation of Earnings Per Share (Detail)

v3.8.0.1
Net Loss Per Share - Schedule of Anti-dilutive Securities Excluded from Computation of Earnings Per Share (Detail) - shares
shares in Thousands
3 Months Ended
Apr. 30, 2018
Apr. 30, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Anti-dilutive potentially outstanding common shares 4,096 3,246
Stock Options [Member]    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Anti-dilutive potentially outstanding common shares 3,195 1,698
Restricted Stock Units [Member]    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Anti-dilutive potentially outstanding common shares 387 1,126
Deferred Stock Units [Member]    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Anti-dilutive potentially outstanding common shares 163 106
Performance Stock Units (PSUs) [Member]    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Anti-dilutive potentially outstanding common shares 351 316