cm:Level2TextBlock: us-gaap:InternalReplacementsOfInsuranceContractsPolicy
| Internal Replacements of Insurance Contracts, Policy [Policy Text Block] |
| us-gaap:InternalReplacementsOfInsuranceContractsPolicy |
| Disclosure of accounting policy for previously deferred policy acquisition costs and previously deferred sales inducements when internal replacements of insurance contracts occur, including whether or not the entity has availed itself of the alternative guidance permitted under GAAP, and, if so, for which types of internal replacement transactions. |
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| us-gaap:InternalReplacementsOfInsuranceContractsPolicy |