| Standard label: | Liability for Future Policy Benefit, Adverse Development, Expense |
| Name: | us-gaap:LiabilityForFuturePolicyBenefitAdverseDevelopmentExpense |
| Documentation: | Amount of expense for adverse development on liability of future policy benefit from net premium exceeding gross premium. |
| Object type: | cm:Concept |
| Data type: | Monetary (xbrli:monetaryItemType) |
| Period type: | For Period (duration) |
| Balance type: | Debit |
| Abstract: | false |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:LiabilityForFuturePolicyBenefitAdverseDevelopmentExpense |
| Label | Role | Language |
| Liability for Future Policy Benefit, Adverse Development, Expense | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 944 40 65 2 (g)(2)(ii) | http://www.xbrl.org/2003/role/exampleRef | 944 |
| FASB Accounting Standards Codification 944 40 50 6 (d) | http://www.xbrl.org/2003/role/disclosureRef | 944 |