cm:Member: us-gaap:NonredeemableConvertiblePreferredStockMember
| Nonredeemable Convertible Preferred Stock [Member] |
| us-gaap:NonredeemableConvertiblePreferredStockMember |
| Capital stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity and may be exchanged into common shares or other types of securities at the owner's option as long as it is in accordance with the issuer's terms. This security does not have redemption requirements. |
| cm:Member |
| [Member] (nonnum:domainItemType) |
| For Period (duration) |
| (no balance type) |
| true |
| us-gaap:NonredeemableConvertiblePreferredStockMember |