CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - $ / shares |
Sep. 30, 2019 |
Dec. 31, 2018 |
|---|---|---|
| Class of Stock [Line Items] | ||
| Preferred stock, par value (in USD per share) | $ 0.0000001 | $ 0.0000001 |
| Preferred stock, shares authorized (in shares) | 100,000,000 | 100,000,000 |
| Preferred stock, shares issued (in shares) | 0 | 0 |
| Preferred stock, shares outstanding (in shares) | 0 | 0 |
| Class A | ||
| Class of Stock [Line Items] | ||
| Common stock, par value (in USD per share) | $ 0.0000001 | $ 0.0000001 |
| Common stock, shares authorized (in shares) | 1,000,000,000 | 1,000,000,000 |
| Common stock, shares issued (in shares) | 346,552,092 | 323,546,864 |
| Common stock, shares outstanding (in shares) | 346,552,092 | 323,546,864 |
| Class B | ||
| Class of Stock [Line Items] | ||
| Common stock, par value (in USD per share) | $ 0.0000001 | $ 0.0000001 |
| Common stock, shares authorized (in shares) | 500,000,000 | 500,000,000 |
| Common stock, shares issued (in shares) | 82,521,716 | 93,501,142 |
| Common stock, shares outstanding (in shares) | 82,521,716 | 93,501,142 |