cm:Level2TextBlock: us-gaap:CapitalizationOfDeferredPolicyAcquisitionCostsPolicy
| Deferred Policy Acquisition Costs, Policy [Policy Text Block] |
| us-gaap:CapitalizationOfDeferredPolicyAcquisitionCostsPolicy |
| Disclosure of accounting policy for deferred policy acquisition costs, including the nature, type, and amount of capitalized costs incurred to write or acquire insurance contracts, and the basis for and methodologies applied in capitalizing and amortizing such costs. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
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| us-gaap:CapitalizationOfDeferredPolicyAcquisitionCostsPolicy |