cm:Concept: us-gaap:OtherRealEstateOwnedFairValueByFairValueHierarchyLevelExtensibleList
| Other Real Estate Owned, Fair Value by Fair Value Hierarchy Level [Extensible List] |
| us-gaap:OtherRealEstateOwnedFairValueByFairValueHierarchyLevelExtensibleList |
| Indicates level within fair value hierarchy of real estate owned by financial institution which is not directly related to its business. |
| cm:Concept |
| srt-types:extensibleListItemType |
| As Of (instant) |
| (no balance type) |
| false |
| us-gaap:OtherRealEstateOwnedFairValueByFairValueHierarchyLevelExtensibleList |