cm:Member: us-gaap:DerivativeFinancialInstrumentsLiabilitiesMember
| Derivative Financial Instruments, Liabilities [Member] |
| us-gaap:DerivativeFinancialInstrumentsLiabilitiesMember |
| This item represents derivative instrument obligations meeting the definition of a liability which are reported as of the balance sheet date. Derivative instrument obligations are generally measured at fair value, and adjustments to the carrying amount of hedged items reflect changes in their fair value (that is, losses) that are attributable to the risk being hedged and that arise while the hedge is in effect. |
| cm:Member |
| [Member] (nonnum:domainItemType) |
| For Period (duration) |
| (no balance type) |
| true |
| us-gaap:DerivativeFinancialInstrumentsLiabilitiesMember |