cm:Concept: us-gaap:LongDurationContractsAssumptionsByProductAndGuaranteeLapseRate
| Long-Duration Contracts, Assumptions by Product and Guarantee, Lapse Rate |
| us-gaap:LongDurationContractsAssumptionsByProductAndGuaranteeLapseRate |
| Anticipated rate of future terminations of contracts in force as of the balance sheet date, which is included in determining the amount of the specified guaranteed benefit obligation as of the balance sheet date. |
| cm:Concept |
| Percent (num:percentItemType) |
| As Of (instant) |
| (no balance type) |
| false |
| us-gaap:LongDurationContractsAssumptionsByProductAndGuaranteeLapseRate |