Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity - Fair Value of Stock Options Granted (Detail)

v3.19.1
Stockholders' Equity - Fair Value of Stock Options Granted (Detail)
12 Months Ended
Jan. 31, 2019
Jan. 31, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]    
Risk-free interest rate 2.60% 2.40%
Expected volatility 46.80% 41.00%
Expected dividend yield 0.00% 0.00%
Expected term (in years) 6 years 6 years