| **Derivative Accounting - Schedule of Gross Notional Amounts Outstanding (Details) - Commodity Contracts MWh in Thousands, MMcf in Thousands** |        | 3 Months Ended |
|------------------------------------------------------------------------------------------------------------------------------------------------|--------|----------------|
||
| **Outstanding gross notional amount of derivatives**                                                                                           |   |           |
| Power | MWh                                                                                                                                    | 583    | 287            |
| Gas | MMcf                                                                                                                                     | 240    | 192            |

| X                                                                                                                                                                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Nominal energy measure used to calculate payments on a derivative instrument.
+ References
No definition available.
+ Details**Name:**us-gaap_DerivativeNonmonetaryNotionalAmountEnergyMeasure**Namespace Prefix:**us-gaap_**Data Type:**num:energyItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                    |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Nominal volume used to calculate payments on a derivative instrument.
+ References
No definition available.
+ Details**Name:**us-gaap_DerivativeNonmonetaryNotionalAmountVolume**Namespace Prefix:**us-gaap_**Data Type:**num:volumeItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - References
No definition available.
+ Details**Name:**us-gaap_NotionalAmountOfDerivativesAbstract**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_DerivativeInstrumentRiskAxis=us-gaap_CommodityContractMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |