cm:Level3TextBlock: us-gaap:ScheduleOfGainContingenciesByContingencyTextBlock
| Schedule of Gain Contingencies by Contingency [Table Text Block] |
| us-gaap:ScheduleOfGainContingenciesByContingencyTextBlock |
| Tabular disclosure of an existing condition, situation, or set of circumstances involving uncertainty as of the balance sheet date (or prior to issuance of the financial statements) that might result in a gain, typically reflecting care to avoid misleading implications as to the likelihood of realization, and describes and quantifies a gain recognized in the period resulting from resolution of a previously disclosed gain contingency. |
| cm:Level3TextBlock |
| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:ScheduleOfGainContingenciesByContingencyTextBlock |
| GainContingenciesByContingency |