cm:Concept: us-gaap:FiniteLivedIntangibleAssetsCostIncurredToRenewOrExtend
| Finite-Lived Intangible Assets, Cost Incurred to Renew or Extend |
| us-gaap:FiniteLivedIntangibleAssetsCostIncurredToRenewOrExtend |
| The amount of capitalized costs incurred in the period to renew or extend the term of a recognized finite-lived (amortizing and amortizable) intangible asset. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| For Period (duration) |
| Debit |
| false |
| us-gaap:FiniteLivedIntangibleAssetsCostIncurredToRenewOrExtend |