| Standard label: | Multiemployer Plan Name [Axis] |
| Name: | us-gaap:MultiemployerPlanNameAxis |
| Documentation: | Information by legal name of a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. |
| Object type: | cm:Axis |
| Data type: | Text/String (xbrli:stringItemType) |
| Period type: | For Period (duration) |
| Balance type: | (no balance type) |
| Abstract: | true |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:MultiemployerPlanNameAxis |
| Label | Role | Language |
| Multiemployer Plan Name [Axis] | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 715 80 50 5 (a) | http://fasb.org/us-gaap/role/ref/legacyRef | 715 |