Revenue Recognition - Passenger Revenue (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2020 |
Sep. 30, 2019 |
Sep. 30, 2020 |
Sep. 30, 2019 |
|
| Disaggregation of Revenue [Line Items] | ||||
| Operating revenue | $ 3,062 | $ 12,560 | $ 13,122 | $ 35,568 |
| Passenger | ||||
| Disaggregation of Revenue [Line Items] | ||||
| Operating revenue | 1,938 | 11,410 | 10,185 | 32,032 |
| Ticket | ||||
| Disaggregation of Revenue [Line Items] | ||||
| Operating revenue | 1,634 | 10,029 | 8,712 | 27,986 |
| Loyalty travel awards | ||||
| Disaggregation of Revenue [Line Items] | ||||
| Operating revenue | 143 | 732 | 731 | 2,174 |
| Travel-related services | ||||
| Disaggregation of Revenue [Line Items] | ||||
| Operating revenue | $ 161 | $ 649 | $ 742 | $ 1,872 |