Accounting For Suspended Exploratory Well Costs (Change In Capitalized Suspended Exploratory Well Costs) (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
|
| Accounting For Suspended Exploratory Well Costs [Abstract] | |||
| Balance beginning at January 1 | $ 4,160 | $ 3,700 | $ 4,477 |
| Additions pending the determination of proved reserves | 532 | 564 | 906 |
| Charged to expense | (46) | (7) | (1,205) |
| Reclassifications to wells, facilities and equipment based on the determination of proved reserves | (37) | (48) | (497) |
| Divestments/Other | 4 | (49) | 19 |
| Ending balance at December 31 | 4,613 | 4,160 | 3,700 |
| Ending balance attributed to equity companies included above | $ 306 | $ 306 | $ 306 |