cm:Level3TextBlock: us-gaap:CostIncurredInOilAndGasPropertyAcquisitionExplorationAndDevelopmentActivitiesDisclosureTextBlock
| Cost Incurred in Oil and Gas Property Acquisition, Exploration, and Development Activities Disclosure [Table Text Block] |
| us-gaap:CostIncurredInOilAndGasPropertyAcquisitionExplorationAndDevelopmentActivitiesDisclosureTextBlock |
| Tabular disclosure of the aggregate of costs (whether the costs are capitalized or charged to expense at the time they are incurred ) incurred for the year in oil and gas property acquisition, exploration and development activities. |
| cm:Level3TextBlock |
| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:CostIncurredInOilAndGasPropertyAcquisitionExplorationAndDevelopmentActivitiesDisclosureTextBlock |