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Stockholders' Equity - Schedule of Weighted-Average Assumptions Used to Estimate Fair Value of Options Granted (Detail)
12 Months Ended
Jan. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Volatility, Minimum 42.00% 42.00% 57.00%
Volatility, Maximum 50.00% 55.00% 65.00%
Risk-free interest rate, Minimum 1.03% 0.83% 1.18%
Risk-free interest rate, Maximum 2.09% 1.15% 2.72%
Dividend yield         
Minimum [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected life (in years) 6 years 3 months 26 days    
Maximum [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected life (in years) 8 years 2 months 19 days 6 years 3 months 26 days 6 years 3 months 26 days