cm:Level3TextBlock: us-gaap:PresentValueOfFutureInsuranceProfitsExpectedAmortizationTableTextBlock
| Present Value of Future Insurance Profits, Expected Amortization [Table Text Block] |
| us-gaap:PresentValueOfFutureInsuranceProfitsExpectedAmortizationTableTextBlock |
| Tabular disclosure of amount of amortization expense expected to be recorded in succeeding fiscal years for present value of future profits of insurance contract acquired in business combination. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
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| us-gaap:PresentValueOfFutureInsuranceProfitsExpectedAmortizationTableTextBlock |