| Standard label: | Performing Financial Instruments [Member] |
| Name: | us-gaap:PerformingFinancingReceivableMember |
| Documentation: | Category status of financial instruments in which payments are received or paid on a timely basis in accordance with the terms of the contract. Financial instruments include, but are not limited to, financing receivables, loans, debt instruments, and investments. |
| Object type: | cm:Member |
| Data type: | [Member] (nonnum:domainItemType) |
| Period type: | For Period (duration) |
| Balance type: | (no balance type) |
| Abstract: | true |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:PerformingFinancingReceivableMember |
| Label | Role | Language |
| Performing Financial Instruments [Member] | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 310 10 50 29 | http://fasb.org/us-gaap/role/ref/legacyRef | 310 |
| FASB Accounting Standards Codification 326 20 50 5 | http://www.xbrl.org/2009/role/commonPracticeRef | 326 |