cm:Concept: us-gaap:LossContingencyUndiscountedAmountOfInsuranceRelatedAssessmentLiability
| Loss Contingency, Undiscounted Amount of Insurance-related Assessment Liability |
| us-gaap:LossContingencyUndiscountedAmountOfInsuranceRelatedAssessmentLiability |
| The liability as of the balance sheet date representing required funding mandated by statute or regulatory authority that is related directly or indirectly to underwriting activities, including pools for self-insurance and excluding premium taxes and income taxes. The funds derived from the assessments generally enable a government guarantor to pay insurance claims in the event that the underwriting insurer is insolvent or otherwise unable to meet its payment obligations. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| For Period (duration) |
| Credit |
| false |
| us-gaap:LossContingencyUndiscountedAmountOfInsuranceRelatedAssessmentLiability |