cm:Concept: us-gaap:AmountOfRestrictedNetAssetsForConsolidatedAndUnconsolidatedSubsidiaries
| Amount of Restricted Net Assets for Consolidated and Unconsolidated Subsidiaries |
| us-gaap:AmountOfRestrictedNetAssetsForConsolidatedAndUnconsolidatedSubsidiaries |
| Amount of restricted net assets of consolidated and unconsolidated subsidiaries as of the end of the most recently completed fiscal year. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Debit |
| false |
| us-gaap:AmountOfRestrictedNetAssetsForConsolidatedAndUnconsolidatedSubsidiaries |