cm:Level2TextBlock: us-gaap:ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock
| Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block] |
| us-gaap:ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock |
| Disclosure of accounting policy for recognizing and measuring the impairment of long-lived assets. An entity also may disclose its accounting policy for long-lived assets to be sold. This policy excludes goodwill and intangible assets. |
| cm:Level2TextBlock |
| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock |