| Standard label: | Other Underwriting Expense |
| Name: | us-gaap:OtherUnderwritingExpense |
| Documentation: | Costs incurred during the period, such as those relating to general administration and policy maintenance that do not vary with and are not primarily related to the acquisition or renewal of insurance contracts. |
| 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:OtherUnderwritingExpense |
| Label | Role | Language |
| Other Underwriting Expense | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 944 220 S99 1 (SX 210.7-04.7) | http://fasb.org/us-gaap/role/ref/legacyRef | 944 |
| FASB Accounting Standards Codification 944 720 25 2 | http://fasb.org/us-gaap/role/ref/legacyRef | 944 |
| Part Of Roll Up: |
| us-gaap:OperatingExpenses |