cm:Member: us-gaap:GuaranteedMinimumWithdrawalBenefitMember
| Guaranteed Minimum Withdrawal Benefit [Member] |
| us-gaap:GuaranteedMinimumWithdrawalBenefitMember |
| Feature in an insurance contract that allows the contract holder to, at a minimum, withdraw a fixed percentage of the annuity premiums on a periodic basis regardless of market performance until the premium is recovered. |
| cm:Member |
| [Member] (nonnum:domainItemType) |
| For Period (duration) |
| (no balance type) |
| true |
| us-gaap:GuaranteedMinimumWithdrawalBenefitMember |