| Standard label: | Schedule of Minimum Guaranteed Benefit Liabilities [Table Text Block] |
| Name: | us-gaap:ScheduleOfMinimumGuaranteedBenefitLiabilitiesTextBlock |
| Documentation: | Tabular disclosure of minimum guaranteed benefits to policyholders and contract holders, such as guaranteed minimum death benefit, guaranteed minimum income benefit, and guaranteed annuitization benefits, discloses the amount of liability reported for additional insurance benefits, annuitization benefits and other minimum guarantees, by type of benefit, for the most recent balance sheet date and the incurred and paid amounts for periods presented for traditional and nontraditional products. |
| Object type: | cm:Level3TextBlock |
| 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:ScheduleOfMinimumGuaranteedBenefitLiabilitiesTextBlock |
| Label | Role | Language |
| Schedule of Minimum Guaranteed Benefit Liabilities [Table Text Block] | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 944 20 55 15 | http://fasb.org/us-gaap/role/ref/legacyRef | 944 |
| FASB Accounting Standards Codification 944 80 50 1 (d) | http://fasb.org/us-gaap/role/ref/legacyRef | 944 |