| Standard label: | Revenue from Contract with Customer [Text Block] |
| Name: | us-gaap:RevenueFromContractWithCustomerTextBlock |
| Documentation: | The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts. |
| Object type: | cm:Level1TextBlock |
| Data type: | Text Block (HTML) (nonnum:textBlockItemType) |
| Period type: | For Period (duration) |
| Balance type: | (no balance type) |
| Abstract: | false |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:RevenueFromContractWithCustomerTextBlock |
| Label | Role | Language |
| Revenue from Contract with Customer [Text Block] | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 606 | http://www.xbrl.org/2003/role/disclosureRef | 606 |