Non-Mineral Leases - Balance Sheet Liabilities (Details) $ in Millions |
Dec. 31, 2019
USD ($)
|
|---|---|
| Finance Lease, Liability Total | $ 720 |
| Operating Lease, Liability | 932 |
| Short Term Debt [Member] | |
| Finance Lease, Liability Total | 87 |
| Other Liabilities and deferred credits [Member] | |
| Operating Lease, Liability | 585 |
| Other Accruals [Member] | |
| Operating Lease, Liability | 347 |
| Long Term Debt Location [Member] | |
| Finance Lease, Liability Total | $ 633 |