| Standard label: | Reinsurance Accounting Policy [Policy Text Block] |
| Name: | us-gaap:ReinsuranceAccountingPolicy |
| Documentation: | Disclosure of reinsurance accounting policy, for example, but not limited to, description of the methodologies and assumptions underlying determination of reinsurance recoverables, reinsurance payables and retention policy. |
| 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:ReinsuranceAccountingPolicy |
| Label | Role | Language |
| Reinsurance Accounting Policy [Policy Text Block] | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 235 10 50 3 | http://fasb.org/us-gaap/role/ref/legacyRef | 235 |
| FASB Accounting Standards Codification 944 20 50 3 | http://fasb.org/us-gaap/role/ref/legacyRef | 944 |
| FASB Accounting Standards Codification 944 20 50 4 | http://fasb.org/us-gaap/role/ref/legacyRef | 944 |
| FASB Accounting Standards Codification 944 210 S99 1 (SX 210.7-03.13(c)) | http://fasb.org/us-gaap/role/ref/legacyRef | 944 |
| FASB Accounting Standards Codification 944 605 55 12 | http://fasb.org/us-gaap/role/ref/legacyRef | 944 |
| FASB Accounting Standards Codification 944 605 55 15 | http://fasb.org/us-gaap/role/ref/legacyRef | 944 |