| Standard label: | Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Reclassification Adjustment, before Tax |
| Name: | us-gaap:DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeLossNetGainLossBeforeTax |
| Documentation: | Amount, before tax, after reclassification adjustment, of increase (decrease) in accumulated other comprehensive income from gain (loss) 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:DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeLossNetGainLossBeforeTax |
| Label | Role | Language |
| Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Reclassification Adjustment, before Tax | http://www.xbrl.org/2003/role/label | en-US |
| Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Reclassification Adjustment, before Tax, Total | http://www.xbrl.org/2003/role/totalLabel | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 220 10 45 10A (i) | http://fasb.org/us-gaap/role/ref/legacyRef | 220 |
| FASB Accounting Standards Codification 220 10 45 11 | http://fasb.org/us-gaap/role/ref/legacyRef | 220 |
| FASB Accounting Standards Codification 715 20 50 1 (i) | http://fasb.org/us-gaap/role/ref/legacyRef | 715 |