| Standard label: | Short-term Leases [Policy Text Block] |
| Name: | us-gaap:ShortTermLeasesPolicyTextBlock |
| Documentation: | Disclosure of accounting policy election for short-term lease to recognize lease payments on straight-line basis over lease term and variable lease payments as incurred. |
| Object type: | cm:Level2TextBlock |
| 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:ShortTermLeasesPolicyTextBlock |
| Label | Role | Language |
| Short-term Leases [Policy Text Block] | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 842 20 25 2 | http://www.xbrl.org/2003/role/disclosureRef | 842 |