| Standard label: | Accumulated Defined Benefit Plans Adjustment, Net Transition Attributable to Parent [Member] | 
| Name: | us-gaap:AccumulatedDefinedBenefitPlansAdjustmentNetTransitionAssetObligationMember | 
| Documentation: | Accumulated other comprehensive income (loss) related to transition asset (obligation) component of defined benefit plans attributable to the parent. | 
| Object type: | cm:Member | 
| Data type: | [Member] (nonnum:domainItemType) | 
| Period type: | For Period (duration) | 
| Balance type: | (no balance type) | 
| Abstract: | true | 
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:AccumulatedDefinedBenefitPlansAdjustmentNetTransitionAssetObligationMember | 
| Label | Role | Language | 
| Accumulated Defined Benefit Plans Adjustment, Net Transition Attributable to Parent [Member] | http://www.xbrl.org/2003/role/label | en-US | 
| Reference | Role | Topic | 
| FASB Accounting Standards Codification 220 10 45 14A | http://fasb.org/us-gaap/role/ref/legacyRef | 220 | 
| FASB Accounting Standards Codification 220 10 45 17B | http://www.xbrl.org/2003/role/disclosureRef | 220 | 
| FASB Accounting Standards Codification 220 10 45 10A (k) | http://fasb.org/us-gaap/role/ref/legacyRef | 220 | 
| FASB Accounting Standards Codification 715 20 50 1 (i),(j) | http://fasb.org/us-gaap/role/ref/legacyRef | 715 | 
| FASB Accounting Standards Codification 810 10 50 1A (c),(3) | http://fasb.org/us-gaap/role/ref/legacyRef | 810 |