Revenue Recognition - Trade allowance for credit losses - NEW (Details) - USD ($) $ in Millions |
6 Months Ended | 12 Months Ended |
|---|---|---|
Jun. 30, 2020 |
Dec. 31, 2019 |
|
| Roll forward of notes and accounts receivable - trade allowance for credit losses | ||
| Allowance for Credit Loss, Beginning Balance | $ 299 | $ 309 |
| Additions / (Releases) | 87 | 98 |
| Write-offs | (26) | (113) |
| Other | (8) | 5 |
| Allowance for Credit Loss, Ending Balance | 369 | 299 |
| Cumulative Effect, Period of Adoption, Adjustment | ||
| Roll forward of notes and accounts receivable - trade allowance for credit losses | ||
| Allowance for Credit Loss, Beginning Balance | $ 316 | |
| Allowance for Credit Loss, Ending Balance | $ 316 |