Equity Incentive Plans and Employee Stock Purchase Plan - Schedule of Stock Option Activity (Details) - USD ($)
$ / shares in Units, $ in Thousands |
3 Months Ended |
12 Months Ended |
Apr. 30, 2019 |
Jan. 31, 2019 |
| Shares |
|
|
| Balance - beginning of period (in shares) |
8,621,010
|
|
| Stock options exercised (in shares) |
(831,901)
|
|
| Stock options forfeited and expired (in shares) |
(77,121)
|
|
| Balance - end of period (in shares) |
7,711,988
|
8,621,010
|
| Vested and exercisable (in shares) |
4,917,890
|
5,342,183
|
| Weighted- Average Exercise Price Per Share |
|
|
| Balance - beginning of period (in dollars per share) |
$ 7.75
|
|
| Stock options exercised (in dollars per share) |
7.71
|
|
| Stock options forfeited and expired (in dollars per share) |
10.45
|
|
| Balance - end of period (in dollars per share) |
7.73
|
$ 7.75
|
| Vested and exercisable (in dollars per share) |
$ 6.95
|
$ 6.95
|
| Weighted- Average Remaining Contractual Term (In Years) |
|
|
| Balance |
6 years 6 months 11 days
|
6 years 8 months 12 days
|
| Vested and exercisable |
5 years 10 months 28 days
|
6 years
|
| Aggregate Intrinsic Value |
|
|
| Balance |
$ 1,027,149
|
$ 729,392
|
| Vested and exercisable |
$ 658,851
|
$ 456,275
|