| Standard label: | Liability, Other Postretirement Defined Benefit Plan, Noncurrent |
| Name: | us-gaap:OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent |
| Documentation: | Amount of liability, recognized in statement of financial position, for defined benefit other postretirement plan, classified as noncurrent. Excludes pension plan. |
| Object type: | cm:Concept |
| Data type: | Monetary (xbrli:monetaryItemType) |
| Period type: | As Of (instant) |
| Balance type: | Credit |
| Abstract: | false |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent |
| Label | Role | Language |
| Liability, Other Postretirement Defined Benefit Plan, Noncurrent | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 210 10 S99 1 (SX 210.5-02(24)) | http://fasb.org/us-gaap/role/ref/legacyRef | 210 |
| FASB Accounting Standards Codification 715 20 50 1 (c) | http://fasb.org/us-gaap/role/ref/legacyRef | 715 |
| FASB Accounting Standards Codification 715 20 45 2 | http://fasb.org/us-gaap/role/ref/legacyRef | 715 |
| FASB Accounting Standards Codification 715 20 45 3 | http://fasb.org/us-gaap/role/ref/legacyRef | 715 |
| Part Of Roll Up: |
| us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent |