Balance Sheet Components - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands |
Dec. 31, 2019 |
Dec. 31, 2018 |
|---|---|---|
| Property Plant And Equipment [Line Items] | ||
| Total property and equipment | $ 135,674 | $ 44,944 |
| Accumulated depreciation and amortization | (32,412) | (19,680) |
| Property and Equipment, net | 103,262 | 25,264 |
| Computer and Equipment | ||
| Property Plant And Equipment [Line Items] | ||
| Total property and equipment | 23,834 | 16,056 |
| Leasehold Improvements | ||
| Property Plant And Equipment [Line Items] | ||
| Total property and equipment | 93,239 | 18,396 |
| Website and Internal-Use Software | ||
| Property Plant And Equipment [Line Items] | ||
| Total property and equipment | 6,510 | 6,423 |
| Office Equipment and Furniture | ||
| Property Plant And Equipment [Line Items] | ||
| Total property and equipment | $ 12,091 | $ 4,069 |