cm:Concept: us-gaap:LessorLeasePolicyElectionSalesTaxAndOtherSimilarTax
| Lessor, Lease Policy Election, Sales Tax and Other Similar Tax [true false] |
| us-gaap:LessorLeasePolicyElectionSalesTaxAndOtherSimilarTax |
| Indicates (true false) whether accounting policy was elected to exclude from measurement of lease revenue and associated tax expense tax assessed by governmental authority that was both imposed on and concurrent with specific lease transaction, and collected by lessor. |
| cm:Concept |
| Yes/No (xbrli:booleanItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:LessorLeasePolicyElectionSalesTaxAndOtherSimilarTax |