| Standard label: | Insurance Contract, Acquisition Cost [Policy Text Block] |
| Name: | us-gaap:InsuranceContractAcquisitionCostPolicyTextBlock |
| Documentation: | Disclosure of accounting policy for cost related directly to successful acquisition of new and renewal of insurance contract. Information includes, but is not limited to, input, judgment, assumption, and method used to determine amortization amount, and change in input, judgment, and assumption. Cost, includes but is not limited to, deferred policy acquisition cost, deferred sale inducement cost, and present value of future profit of insurance contract acquired in business combination. |
| Object type: | cm:Level2TextBlock |
| Data type: | Text Block (HTML) (nonnum:textBlockItemType) |
| Period type: | For Period (duration) |
| Balance type: | (no balance type) |
| Abstract: | false |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:InsuranceContractAcquisitionCostPolicyTextBlock |
| Label | Role | Language |
| Insurance Contract, Acquisition Cost [Policy Text Block] | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 944 30 50 2A (b) | http://www.xbrl.org/2003/role/disclosureRef | 944 |
| FASB Accounting Standards Codification 944 30 50 1 (b) | http://www.xbrl.org/2003/role/disclosureRef | 944 |