Income Taxes (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||||||
|---|---|---|---|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Income Tax Disclosure [Abstract] | ||||||||
| Tax Jurisdiction of Domicile [Extensible Enumeration] | UNITED STATES | |||||||
| Income before income taxes (domestic) | $ 69 | $ 55 | $ 205 | $ 143 | ||||
| Federal statutory rate impact | 43 | 30 | ||||||
| Other | (1) | (1) | ||||||
| AFUDC equity | [1] | (4) | (4) | |||||
| Plant related excess deferred taxes | [1] | (2) | (2) | |||||
| Effective Income Tax Reconciliation, Other Regulatory Adjustments, Amount [Abstract] | [1] | 1 | 1 | |||||
| State income taxes, net of federal tax effect (b) | [2] | 12 | 7 | |||||
| Other | (1) | 1 | ||||||
| Income tax expense | $ 16 | $ 12 | $ 48 | $ 32 | ||||
| Federal statutory rate | 21.00% | 21.00% | ||||||
| Other | (0.50%) | (0.40%) | ||||||
| AFUDC equity | [1] | (2.10%) | (2.50%) | |||||
| Plant related excess deferred taxes | [1] | (0.80%) | (1.40%) | |||||
| Other | [1] | 0.30% | 0.40% | |||||
| State income taxes, net of federal tax effect (b) | [2] | 6.00% | 5.30% | |||||
| Other | (0.50%) | 0.00% | ||||||
| Effective income tax rate | 23.40% | 22.40% | ||||||
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- Definition Effective Income Tax Rate Reconciliation, AFUDC Equity, Amount No definition available.
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- Definition Effective Income Tax Rate Reconciliation, AFUDC Equity, Percent No definition available.
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- Definition Effective Income Tax Rate Reconciliation, Other Regulatory Adjustments, Percent No definition available.
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- Definition Effective Income Tax Rate Reconciliation, Plant Related Excess Deferred Taxes, Amount No definition available.
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- Definition Effective Income Tax Rate Reconciliation, Plant Related Excess Deferred Taxes, Percent No definition available.
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- Definition Effective Income Tax Reconciliation, Other Regulatory Adjustments, Amount 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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| X | ||||||||||
- 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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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| X | ||||||||||
- Definition Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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| X | ||||||||||
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Amount 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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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| X | ||||||||||
- Definition Amount 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 state and local income tax expense (benefit). Reference 1: http://www.xbrl.org/2003/role/exampleRef
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| X | ||||||||||
- Definition Amount 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. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Indicates tax jurisdiction of domicile. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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