Stockholder's Equity - Stock-Based Compensation Expense (Details) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Mar. 31, 2020 |
Mar. 31, 2019 |
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Share-based compensation expense | $ 277 | $ 11 |
| Operations and support | ||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Share-based compensation expense | 25 | 1 |
| Sales and marketing | ||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Share-based compensation expense | 14 | 1 |
| Research and development | ||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Share-based compensation expense | 167 | 3 |
| General and administrative | ||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Share-based compensation expense | $ 71 | $ 6 |