Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity - Additional Information (Detail)

v3.7.0.1
Stockholders' Equity - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Millions
1 Months Ended 12 Months Ended
Apr. 06, 2016
Jun. 30, 2016
Jul. 31, 2015
Jan. 31, 2017
Jan. 31, 2016
Jan. 31, 2015
Jul. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Preferred stock, shares authorized       5,000,000      
Preferred stock, shares issued       0      
Expected dividend yield       0.00% 0.00% 0.00%  
Employee service share-based compensation, nonvested awards, total compensation cost not yet recognized       $ 1.4      
Market based options granted       1,581,614 612,678 500,000  
Share-based compensation arrangement by share-based payment award, options, grants in period, weighted average grant date fair value       $ 3.09 $ 2.75 $ 3.39  
Share based compensation arrangement by share based payment award estimated weighted average amortization period       2 years      
Aggregate intrinsic value for options outstanding       $ 0.0 $ 0.1 $ 0.1  
Aggregate intrinsic value of vested shares and share options expected to vest       $ 0.0 0.1 $ 0.1  
Employee service share-based compensation, cash received from exercise of stock options         $ 0.2    
Stock options exercised       0 28,740 0  
Officer [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Share-based compensation arrangement by share-based payment award, options, vested in period, fair value       $ 2.1      
Share-based compensation arrangement by share-based payment award, options, vested in period       2 years 3 months 18 days      
Employee service share-based compensation, nonvested awards, total compensation cost not yet recognized       $ 0.9      
CEO [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Market based options granted 600,000     800,000      
Chief Operating Officer [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Market based options granted   200,000          
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       $ 3.0      
Share based compensation arrangement by share based payment award estimated weighted average amortization period       1 year 3 months 18 days      
Performance Stock Units (PSUs) [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of stock units granted       307,963 301,192    
Fair value of stock units granted       $ 2.9      
Fair value of stock units granted, remaining contractual term       3 years      
Performance Stock Units (PSUs) [Member] | Maximum [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Percentage of common stock expected to be issued       150.00% 150.00%    
Performance Stock Units (PSUs) [Member] | Minimum [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Percentage of common stock expected to be issued       0.00% 0.00%    
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, Description       On each purchase date, eligible employees will 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.      
Minimum payroll deductions at base compensation under employee stock purchase plan     1.00%        
Maximum payroll deductions at base compensation under employee stock purchase plan     15.00%        
Offering period commence date     Oct. 01, 2015        
Percentage of stock to be purchased under the plan     85.00%        
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        
Compensation and Incentive Plan 2011 [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             5,300,000
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, Option award expiration period       10 years      
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent       100.00%      
Compensation and Incentive Plan 2011 [Member] | Maximum [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Share-based compensation arrangement by Share-based payment award, Option award vesting period       4 years      
Compensation and Incentive Plan 2011 [Member] | Minimum [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Share-based compensation arrangement by Share-based payment award, Option award vesting period       1 year      
Compensation and Incentive Plan 2011 [Member] | Stock Compensation 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       393,403      
Long Term Incentive Program [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Share-based compensation arrangement by Share-based payment award, Option award vesting period         3 years