Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation Expense - Additional Information (Detail)

v3.20.2
Stock-Based Compensation Expense - Additional Information (Detail) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jul. 31, 2020
Apr. 30, 2020
Jul. 31, 2020
Jul. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Options granted   0    
Share-based awards fair value     $ 1.5  
Stock Options [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Options granted     300,998  
Cancelled option awards 184,999 114,260    
Employee service share-based compensation, nonvested awards, total compensation cost not yet recognized $ 1.4   $ 1.4  
Share based compensation arrangement by share based payment award expected weighted average recognition period     1 year 9 months 18 days  
Restricted Stock Units [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Awards granted     607,807  
Stock options and restricted stock units cancelled 49,998 98,841    
Restricted Stock Units and Deferred Stock Units [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Employee service share-based compensation, nonvested awards, total compensation cost not yet recognized $ 1.2   $ 1.2  
Share based compensation arrangement by share based payment award expected weighted average recognition period     1 year 6 months  
Performance Stock Unit [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Employee service share-based compensation, nonvested awards, total compensation cost not yet recognized $ 0.2   $ 0.2  
Share based compensation arrangement by share based payment award expected weighted average recognition period     1 year 7 months 6 days  
2011 Compensation and Incentive Plan [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation arrangement by share-based payment award, Description     Option awards may be granted to employees at an exercise price per share of not less than 100% of the fair market value per common share on the date of the grant.  
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent     100.00%  
Share-based compensation arrangement by share based payment award, Option award expiration period     10 years  
2011 Compensation and Incentive Plan [Member] | Minimum [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation arrangement by Share-based payment award, vesting period     1 year  
2011 Compensation and Incentive Plan [Member] | Maximum [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation arrangement by Share-based payment award, vesting period     3 years  
2011 Compensation and Incentive Plan [Member] | Stock Compensation Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation arrangement by share-based payment award, number of shares authorized 9,300,000   9,300,000  
Share-based compensation arrangement by share-based payment award, number of shares available for grant 2,188,287   2,188,287  
2011 Compensation and Incentive Plan [Member] | Deferred Stock Units [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation arrangement by Share-based payment award, vesting period     1 year  
2015 Employee Stock Purchase Plan [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation arrangement by share-based payment award, number of shares available for grant 1,075,024   1,075,024  
Share-based compensation arrangement by share-based payment award, Description     On each purchase date, eligible employees can purchase our stock at a price per share equal to 85% of the closing price of our common stock on the exercise date, but no less than par value.  
Discount percentage from market price of stock     85.00%  
Shares purchased under ESPP     5,702 7,819
2015 Employee Stock Purchase Plan [Member] | Maximum [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation arrangement by share-based payment award, number of shares authorized 1,150,000   1,150,000