cm:Concept: us-gaap:ChangeInAccountingPrincipleAccountingStandardsUpdateTransitionOptionElectedFixedList
| Change in Accounting Principle, Accounting Standards Update, Transition Option Elected [Fixed List] |
| us-gaap:ChangeInAccountingPrincipleAccountingStandardsUpdateTransitionOptionElectedFixedList |
| Indicates transition method applied for adoption of accounting standards update. Acceptable values are "Retrospective", "Prospective", "Modified Retrospective" and "Modified Prospective". |
| cm:Concept |
| us-types:transitionOptionType |
| As Of (instant) |
| (no balance type) |
| false |
| us-gaap:ChangeInAccountingPrincipleAccountingStandardsUpdateTransitionOptionElectedFixedList |