| Standard label: | Defined Benefit Plan, Amortization of Gain (Loss) |
| Name: | us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses |
| Documentation: | Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. |
| 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:DefinedBenefitPlanAmortizationOfGainsLosses |
| Label | Role | Language |
| Defined Benefit Plan, Amortization of Gain (Loss) | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 715 20 50 1 (h)(4) | http://www.xbrl.org/2003/role/disclosureRef | 715 |
| FASB Accounting Standards Codification 715 20 50 6 (a)(4) | http://www.xbrl.org/2003/role/disclosureRef | 715 |
| FASB Accounting Standards Codification 715 20 55 17 | http://www.xbrl.org/2003/role/exampleRef | 715 |
| Part Of Roll Up: |
| us-gaap:NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent |