cm:Concept: us-gaap:DebtorInPossessionFinancingAmendmentsToArrangementIncreaseDecreaseInAmountArranged
| Debtor-in-Possession Financing, Amendments to Arrangement, Increase (Decrease) in Amount Arranged |
| us-gaap:DebtorInPossessionFinancingAmendmentsToArrangementIncreaseDecreaseInAmountArranged |
| Increase or Decrease over the original amount of debtor-in-possession financing made available, via amendment of the original agreement (but not necessarily all borrowed). |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| For Period (duration) |
| Credit |
| false |
| us-gaap:DebtorInPossessionFinancingAmendmentsToArrangementIncreaseDecreaseInAmountArranged |