cm:Level3TextBlock: us-gaap:FiniteLivedAndIndefiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTableTextBlock
| Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination [Table Text Block] |
| us-gaap:FiniteLivedAndIndefiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTableTextBlock |
| Tabular disclosure of finite-lived and indefinite-lived intangible assets acquired as part of a business combination. |
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| (no balance type) |
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| us-gaap:FiniteLivedAndIndefiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTableTextBlock |