| Standard label: | Nuclear Fuel, Net of Amortization |
| Name: | us-gaap:NuclearFuelNetOfAmortization |
| Documentation: | The carrying amount as of the balance sheet of nuclear fuel held as property plant and equipment. This amount is net of amortization based on the energy produced over the life of the fuel. |
| 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:NuclearFuelNetOfAmortization |
| Label | Role | Language |
| Nuclear Fuel, Net of Amortization | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 210 10 S99 1 (SX 210.5-02.13(b)) | http://fasb.org/us-gaap/role/ref/legacyRef | 210 |