| Standard label: | Defined Benefit Plan, Accumulated Benefit Obligation, Increase (Decrease) for Plan Amendment |
| Name: | us-gaap:DefinedBenefitPlanAccumulatedBenefitObligationIncreaseDecreaseForPlanAmendment |
| Documentation: | Amount of increase (decrease) in accumulated benefit obligation from change in existing term of defined benefit plan or initiation of new 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:DefinedBenefitPlanAccumulatedBenefitObligationIncreaseDecreaseForPlanAmendment |
| Label | Role | Language |
| Defined Benefit Plan, Accumulated Benefit Obligation, Increase (Decrease) for Plan Amendment | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 715 20 50 1 (r) | http://fasb.org/us-gaap/role/ref/legacyRef | 715 |