| Standard label: | Unamortized Loss Reacquired Debt, Noncurrent | 
| Name: | us-gaap:UnamortizedLossReacquiredDebtNoncurrent | 
| Documentation: | Unamortized Loss on Reacquired Debt is the loss incurred upon reacquisition or refinancing of debt, is treated as a deferred charge and amortized over the life of the new debt issued. | 
| Object type: | cm:Concept | 
| Data type: | Monetary (xbrli:monetaryItemType) | 
| Period type: | As Of (instant) | 
| Balance type: | Debit | 
| Abstract: | false | 
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:UnamortizedLossReacquiredDebtNoncurrent | 
| Label | Role | Language | 
| Unamortized Loss Reacquired Debt, Noncurrent | http://www.xbrl.org/2003/role/label | en-US | 
| Reference | Role | Topic | 
| FASB Accounting Standards Codification 210 10 S99 1 (SX 210.5-02.17) | http://fasb.org/us-gaap/role/ref/legacyRef | 210 | 
| Part Of Roll Up: | 
| us-gaap:RegulatedEntityOtherAssetsNoncurrent |