| Standard label: | Investments in and Advance to Affiliate, Noncash Dividend [true false] |
| Name: | us-gaap:InvestmentsInAndAdvancesToAffiliatesNoncashDividendsFlag |
| Documentation: | Indicates a non-cash dividend. Explain the circumstances in the "Schedule of Investments, Investment Notes". |
| Object type: | cm:Concept |
| Data type: | Yes/No (xbrli:booleanItemType) |
| Period type: | For Period (duration) |
| Balance type: | (no balance type) |
| Abstract: | false |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:InvestmentsInAndAdvancesToAffiliatesNoncashDividendsFlag |
| Label | Role | Language |
| Investments in and Advance to Affiliate, Noncash Dividend [true false] | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 946 320 S99 6 (SX 210.12-14(5)(c)) | http://fasb.org/us-gaap/role/ref/legacyRef | 946 |