| Standard label: | Foreign Currency Transactions and Translations Policy [Policy Text Block] |
| Name: | us-gaap:ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock |
| Documentation: | Disclosure of accounting policy for (1) transactions denominated in a currency other than the reporting enterprise's functional currency, (2) translating foreign currency financial statements that are incorporated into the financial statements of the reporting enterprise by consolidation, combination, or the equity method of accounting, and (3) remeasurement of the financial statements of a foreign reporting enterprise in a hyperinflationary economy. |
| 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:ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock |
| Label | Role | Language |
| Foreign Currency Transactions and Translations Policy [Policy Text Block] | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 235 10 50 3 | http://fasb.org/us-gaap/role/ref/legacyRef | 235 |
| FASB Accounting Standards Codification 830 20 50 1 | http://fasb.org/us-gaap/role/ref/legacyRef | 830 |
| FASB Accounting Standards Codification 830 30 50 1 | http://fasb.org/us-gaap/role/ref/legacyRef | 830 |