| Standard label: | Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Plan Amendments, Tax Effect | 
| Name: | us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansPlanAmendmentsTaxEffect | 
| Documentation: | Tax effect of plan amendments that occurred that has not been recognized in net periodic benefit cost. | 
| Object type: | cm:Concept | 
| Data type: | Monetary (xbrli:monetaryItemType) | 
| Period type: | For Period (duration) | 
| Balance type: | Credit | 
| Abstract: | false | 
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansPlanAmendmentsTaxEffect | 
| Label | Role | Language | 
| Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Plan Amendments, Tax Effect | http://www.xbrl.org/2003/role/label | en-US | 
| Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Plan Amendments, Tax Effect, Total | http://www.xbrl.org/2003/role/totalLabel | en-US | 
| Reference | Role | Topic | 
| FASB Accounting Standards Codification 220 10 45 12 | http://fasb.org/us-gaap/role/ref/legacyRef | 220 | 
| Part Of Roll Up: | 
| us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansBeforeReclassificationAdjustmentsTax |