cm:Concept: us-gaap:LiabilitiesSubjectToCompromiseRetainedObligationOfDivestedBusinesses
| Liabilities Subject to Compromise, Retained Obligation of Divested Businesses |
| us-gaap:LiabilitiesSubjectToCompromiseRetainedObligationOfDivestedBusinesses |
| The amount of retained obligations related to divested businesses included in liabilities subject to compromise. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Credit |
| false |
| us-gaap:LiabilitiesSubjectToCompromiseRetainedObligationOfDivestedBusinesses |