cm:Level2TextBlock: us-gaap:SalesInducementsToContractHoldersPolicy
| Sales Inducements to Contract Holders, Policy [Policy Text Block] |
| us-gaap:SalesInducementsToContractHoldersPolicy |
| Disclosure of accounting policy for sales inducements, including the yield enhancement features, such as interest credits and bonuses, given to motivate purchases of insurance products, and description of the nature of the costs deferred and the method for amortizing such deferred costs. |
| cm:Level2TextBlock |
| Text Block (HTML) (nonnum:textBlockItemType) |
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| us-gaap:SalesInducementsToContractHoldersPolicy |