cm:Concept: us-gaap:LiabilityForFuturePolicyBenefitsAndUnpaidClaimsAndClaimsAdjustmentExpense
| Liability for Future Policy Benefits and Unpaid Claims and Claims Adjustment Expense |
| us-gaap:LiabilityForFuturePolicyBenefitsAndUnpaidClaimsAndClaimsAdjustmentExpense |
| The aggregate amount of policy reserves (provided for future obligations including unpaid claims and claims adjustment expenses) and policy benefits (liability for future policy benefits) as of the balance sheet date; grouped amount of all the liabilities associated with the company's insurance policies. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Credit |
| false |
| us-gaap:LiabilityForFuturePolicyBenefitsAndUnpaidClaimsAndClaimsAdjustmentExpense |