| Standard label: | Multiemployer Plans, Certified Zone Status, Extended Amortization Provisions [true false] |
| Name: | us-gaap:MultiemployerPlansCertifiedZoneStatusExtendedAmortizationProvisions |
| Documentation: | Indicates (true false) whether multiemployer plan utilized extended amortization provision affecting calculation of zone status. |
| 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:MultiemployerPlansCertifiedZoneStatusExtendedAmortizationProvisions |
| Label | Role | Language |
| Multiemployer Plans, Certified Zone Status, Extended Amortization Provisions [true false] | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 715 80 50 5 (c) | http://fasb.org/us-gaap/role/ref/legacyRef | 715 |