| Standard label: | Refundable Gas Costs |
| Name: | us-gaap:RefundableGasCosts |
| Documentation: | Gas costs of a regulated entity that are refundable through future rate adjustments. Such costs are a form of a regulatory liabilities and are expected to be refunded in less than one year through rate adjustments. |
| Object type: | cm:Concept |
| Data type: | Monetary (xbrli:monetaryItemType) |
| Period type: | As Of (instant) |
| Balance type: | Credit |
| Abstract: | false |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:RefundableGasCosts |
| Label | Role | Language |
| Refundable Gas Costs | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 210 10 S99 1 (SX 210.5-02.20) | http://fasb.org/us-gaap/role/ref/legacyRef | 210 |
| FASB Accounting Standards Codification 980 405 25 1 (b) | http://fasb.org/us-gaap/role/ref/legacyRef | 980 |