| Standard label: | Defined Benefit Plan, Ultimate Health Care Cost Trend Rate |
| Name: | us-gaap:DefinedBenefitPlanUltimateHealthCareCostTrendRate1 |
| Documentation: | Ultimate trend rate for health care cost for defined benefit postretirement plan. |
| Object type: | cm:Concept |
| Data type: | Percent (num:percentItemType) |
| Period type: | As Of (instant) |
| Balance type: | (no balance type) |
| Abstract: | false |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:DefinedBenefitPlanUltimateHealthCareCostTrendRate1 |
| Label | Role | Language |
| Defined Benefit Plan, Ultimate Health Care Cost Trend Rate | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 715 20 50 1 (l) | http://fasb.org/us-gaap/role/ref/legacyRef | 715 |