cm:Concept: us-gaap:NonconsolidatedLegalEntityFinancialSupportAmount
| Nonconsolidated Legal Entity, Financial Support Amount |
| us-gaap:NonconsolidatedLegalEntityFinancialSupportAmount |
| Amount of financial support provided to a nonconsolidated legal entity that is required to comply with or operate in accordance with requirements that are similar to those included in Rule 2a-7 of the Investment Company Act of 1940 for registered money market funds. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| For Period (duration) |
| Credit |
| false |
| us-gaap:NonconsolidatedLegalEntityFinancialSupportAmount |