Equity Incentive Plans and Employee Stock Purchase Plan - Schedule of Restricted Stock Unit Activity (Details) - Restricted Stock Units (RSUs) - $ / shares |
3 Months Ended | |
|---|---|---|
Apr. 30, 2018 |
Jan. 31, 2018 |
|
| Shares | ||
| Unvested - beginning of period (in dollars per share) | 245,746 | |
| RSUs granted (in shares) | 1,050,660 | |
| RSUs vested (in shares) | (125) | |
| RSUs forfeited and canceled (in shares) | 0 | |
| Unvested - end of period (in dollars per share) | 1,296,281 | |
| Weighted-Average Grant Date Fair Value per RSU | ||
| Unvested (in dollars per share) | $ 37.00 | $ 26.20 |
| RSUs granted (in dollars per share) | 39.52 | |
| RSUs vested (in dollars per share) | 28.87 | |
| RSUs forfeited and canceled (in dollars per share) | $ 0.00 |