cm:Concept: us-gaap:LiquidityArrangementsGuaranteesAndOtherCommitmentsByThirdParties
| Variable Interest Entity, Commitments by Third Parties, Liquidity and Other Arrangements |
| us-gaap:LiquidityArrangementsGuaranteesAndOtherCommitmentsByThirdParties |
| Describes the terms of arrangements (for example, liquidity arrangements, guarantees, or other commitments) by third parties that may affect the fair value or risk of the reporting entity's variable interest in the Variable Interest Entity (VIE). |
| cm:Concept |
| Text/String (xbrli:stringItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:LiquidityArrangementsGuaranteesAndOtherCommitmentsByThirdParties |