| Standard label: | Site Contingency, Loss Exposure in Excess of Accrual, Best Estimate |
| Name: | us-gaap:SiteContingencyLossExposureInExcessOfAccrualBestEstimate |
| Documentation: | Best estimate of the reasonably possible loss exposure in excess of the amount accrued for environmental loss contingencies at an individual site. |
| Object type: | cm:Concept |
| Data type: | Monetary (xbrli:monetaryItemType) |
| Period type: | For Period (duration) |
| Balance type: | Debit |
| Abstract: | false |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:SiteContingencyLossExposureInExcessOfAccrualBestEstimate |
| Label | Role | Language |
| Site Contingency, Loss Exposure in Excess of Accrual, Best Estimate | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 410 30 50 10 (d)(2) | http://fasb.org/us-gaap/role/ref/legacyRef | 410 |