cm:Concept: us-gaap:InvestmentsInAndAdvancesToAffiliatesDividendsOrInterest
| Investments in and Advances to Affiliates, Dividends or Interest |
| us-gaap:InvestmentsInAndAdvancesToAffiliatesDividendsOrInterest |
| Amount of dividends or interest. Give totals for each group. If operations of any controlled companies are different in character from those of the company, group such affiliates (1) within divisions and (2) by type of activities. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| For Period (duration) |
| Credit |
| false |
| us-gaap:InvestmentsInAndAdvancesToAffiliatesDividendsOrInterest |