| **Income Taxes Schedule of Effective Income Tax Rate Reconciliation (Details)** | 12 Months Ended |
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| **Income Taxes [Abstract]**                                                     |            |   |   |
| Federal statutory tax rate                                                      | 35.00%          | 35.00% | 35.00% |
| Federal tax credits                                                             | (18.20%)        | (19.00%) | (11.40%) |
| State and local taxes, net of federal tax benefit                               | 4.80%           | 4.20% | 3.90% |
| Flow through depreciation and cost basis differences                            | 0.20%           | 0.00% | (2.30%) |
| Other                                                                           | (1.20%)         | 0.50% | 0.80% |
| Effective tax rate                                                              | 20.60%          | 20.70% | 26.00% |

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| - Definition
Income Taxes [Abstract]
+ References
No definition available.
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| - Definition
Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Percentage of domestic federal statutory tax rate applicable to pretax income (loss).
+ References
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| - Definition
Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to depreciation.
+ References
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| - Definition
Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments.
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| - Definition
Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).
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| - Definition
Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other tax credits.
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