cm:Concept: us-gaap:DescriptionOfRegulatoryAssistance
| Description of Regulatory Assistance |
| us-gaap:DescriptionOfRegulatoryAssistance |
| Description of the nature and terms of regulatory assistance from a federal regulatory agency in conjunction with either an acquisition of a troubled financial institution, transfer of nonperforming assets to a newly-formed entity, or other reorganization. |
| cm:Concept |
| Text/String (xbrli:stringItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:DescriptionOfRegulatoryAssistance |