Income Taxes - Summary of Income Taxes (Detail) - USD ($) $ in Thousands |
3 Months Ended | |
|---|---|---|
Apr. 30, 2019 |
Apr. 30, 2018 |
|
| Income Tax Disclosure [Abstract] | ||
| Loss before income taxes | $ (16,045) | $ (9,158) |
| Provision for income taxes | $ 1,266 | $ 848 |
| Effective tax rate | (7.90%) | (9.30%) |