| Standard label: | Doubtful [Member] |
| Name: | us-gaap:DoubtfulMember |
| Documentation: | A category of financing receivables that have all the weaknesses inherent in those classified as substandard, with the added characteristic that the weaknesses make collection or liquidation in full, on the basis of currently existing facts, conditions, and values, highly questionable and improbable. |
| 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:DoubtfulMember |
| Label | Role | Language |
| Doubtful [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 |