| Standard label: | Nonqualified Plan [Member] |
| Name: | us-gaap:NonqualifiedPlanMember |
| Documentation: | Plan without tax-exempt status in accordance with applicable tax provision of designated taxing authority. Taxing authority includes, but is not limited to, U.S. Internal Revenue Service (IRS). Includes, but is not limited to, defined benefit and defined contribution plans. |
| 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:NonqualifiedPlanMember |
| Label | Role | Language |
| Nonqualified Plan [Member] | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 715 20 50 2 | http://fasb.org/us-gaap/role/ref/legacyRef | 715 |