Balance Sheet Components (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Jan. 31, 2020 |
Jan. 31, 2019 |
Jan. 31, 2018 |
|
| Property, Plant and Equipment [Line Items] | |||
| Depreciation and amortization expense | $ 23.0 | $ 14.8 | $ 7.1 |
| Amortization | $ 0.5 | $ 0.6 | $ 0.6 |
| Developed technology | |||
| Property, Plant and Equipment [Line Items] | |||
| Useful life | 3 years | ||
| Customer relationships | |||
| Property, Plant and Equipment [Line Items] | |||
| Useful life | 5 years | ||
| Non-compete agreement | |||
| Property, Plant and Equipment [Line Items] | |||
| Useful life | 3 years | ||
| Data center and other computer equipment | |||
| Property, Plant and Equipment [Line Items] | |||
| Equipment additions | $ 44.9 | ||