| Standard label: | US States and Political Subdivisions Debt Securities [Member] |
| Name: | us-gaap:USStatesAndPoliticalSubdivisionsMember |
| Documentation: | Bonds or similar securities issued by state, city, or local US governments or the agencies operated by state, city, or local governments. Debt securities issued by state governments may include bond issuances of US state authorities including, for example, but not limited to, housing authorities, dormitory authorities, and general obligations while debt securities issued by political subdivisions of US states would include, for example, debt issuances by county, borough, city, or municipal governments. |
| Object type: | cm:Member |
| Data type: | [Member] (nonnum:domainItemType) |
| Period type: | For Period (duration) |
| Balance type: | (no balance type) |
| Abstract: | true |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:USStatesAndPoliticalSubdivisionsMember |
| Label | Role | Language |
| US States and Political Subdivisions Debt Securities [Member] | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 715 20 50 1 (d)(ii) | http://www.xbrl.org/2003/role/exampleRef | 715 |
| FASB Accounting Standards Codification 944 80 50 1 (e) | http://www.xbrl.org/2009/role/commonPracticeRef | 944 |