| Standard label: | Unamortized Debt Issuance Expense |
| Name: | us-gaap:UnamortizedDebtIssuanceExpense |
| Documentation: | The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset. |
| 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:UnamortizedDebtIssuanceExpense |
| Label | Role | Language |
| Unamortized Debt Issuance Expense | 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 |