cm:Concept: us-gaap:WeightedAverageNumberOfLimitedPartnershipAndGeneralPartnershipUnitOutstandingBasicAndDiluted
| Weighted Average Number of Limited Partnership and General Partnership Unit Outstanding, Basic and Diluted |
| us-gaap:WeightedAverageNumberOfLimitedPartnershipAndGeneralPartnershipUnitOutstandingBasicAndDiluted |
| The average number of limited partnership and general partnership units issued and outstanding that are used in calculating basic and diluted earnings per limited partnership and general partnership unit. |
| cm:Concept |
| Shares (xbrli:sharesItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:WeightedAverageNumberOfLimitedPartnershipAndGeneralPartnershipUnitOutstandingBasicAndDiluted |