cm:Concept: us-gaap:PreferredStockSharesAuthorizedUnlimited
| Preferred Stock, Shares Authorized, Unlimited [Fixed List] |
| us-gaap:PreferredStockSharesAuthorizedUnlimited |
| Indicates that the number of nonredeemable preferred shares, or preferred stock redeemable solely at the option of the issuer, permitted to be issued by an entity's charter and bylaws is unlimited. The acceptable value is "Unlimited". |
| cm:Concept |
| us-types:authorizedUnlimitedItemType |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:PreferredStockSharesAuthorizedUnlimited |