Fair Value Measurements - Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($)
$ in Thousands |
Apr. 30, 2019 |
Jan. 31, 2019 |
| Cash equivalents: |
|
|
| Total assets |
$ 158,193
|
$ 205,521
|
| Level 1 |
|
|
| Cash equivalents: |
|
|
| Total assets |
158,193
|
203,746
|
| Level 2 |
|
|
| Cash equivalents: |
|
|
| Total assets |
0
|
1,775
|
| Level 3 |
|
|
| Cash equivalents: |
|
|
| Total assets |
0
|
0
|
| Money market funds |
|
|
| Cash equivalents: |
|
|
| Cash equivalents and restricted cash |
158,193
|
203,746
|
| Money market funds | Level 1 |
|
|
| Cash equivalents: |
|
|
| Cash equivalents and restricted cash |
158,193
|
203,746
|
| Money market funds | Level 2 |
|
|
| Cash equivalents: |
|
|
| Cash equivalents and restricted cash |
0
|
0
|
| Money market funds | Level 3 |
|
|
| Cash equivalents: |
|
|
| Cash equivalents and restricted cash |
0
|
0
|
| Certificates of deposit |
|
|
| Cash equivalents: |
|
|
| Cash equivalents and restricted cash |
0
|
1,775
|
| Certificates of deposit | Level 1 |
|
|
| Cash equivalents: |
|
|
| Cash equivalents and restricted cash |
0
|
0
|
| Certificates of deposit | Level 2 |
|
|
| Cash equivalents: |
|
|
| Cash equivalents and restricted cash |
0
|
1,775
|
| Certificates of deposit | Level 3 |
|
|
| Cash equivalents: |
|
|
| Cash equivalents and restricted cash |
$ 0
|
$ 0
|