cm:Concept: us-gaap:IncreaseDecreaseInAccruedCostOfOilAndGasReclamation
| Increase (Decrease) in Accrued Cost of Oil and Gas Reclamation |
| us-gaap:IncreaseDecreaseInAccruedCostOfOilAndGasReclamation |
| The increase (decrease) during the reporting period in accrued costs that represent future cash outlays for restoration and reclamation of oil and gas producing properties. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| For Period (duration) |
| Credit |
| false |
| us-gaap:IncreaseDecreaseInAccruedCostOfOilAndGasReclamation |