| Standard label: | Direct Financing Lease, Lease Income [Table Text Block] |
| Name: | us-gaap:DirectFinancingLeaseLeaseIncomeTableTextBlock |
| Documentation: | Tabular disclosure of components of lease income from direct financing lease. |
| Object type: | cm:Level3TextBlock |
| 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:DirectFinancingLeaseLeaseIncomeTableTextBlock |
| Label | Role | Language |
| Direct Financing Lease, Lease Income [Table Text Block] | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 270 10 50 6A | http://www.xbrl.org/2003/role/disclosureRef | 270 |
| FASB Accounting Standards Codification 842 30 50 5 | http://www.xbrl.org/2003/role/disclosureRef | 842 |