Income Taxes - Summary of Significant Factors Impact on Difference Between Effective Tax Rate and Federal Statutory Rate (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] | ||||
| Income from continuing operations before income tax expense | $ 56 | $ 31 | $ 202 | $ 137 |
| U.S. federal statutory tax rate | $ 11 | $ 7 | $ 42 | $ 29 |
| Tax Jurisdiction of Domicile [Extensible Enumeration] | us-gaap:StateAndLocalJurisdictionMember | us-gaap:StateAndLocalJurisdictionMember | us-gaap:StateAndLocalJurisdictionMember | us-gaap:StateAndLocalJurisdictionMember |
| State income taxes, net of federal income tax effect | $ 0 | $ 0 | $ 1 | $ 1 |
| Flow through related to deduction of meters and mixed service costs | (1) | (1) | (5) | (5) |
| Excess deferred tax amortization | (3) | (2) | (8) | (7) |
| Other | 0 | (2) | (4) | (3) |
| Total other adjustments | (4) | (5) | (17) | (15) |
| Effective tax rate | $ 7 | $ 2 | $ 26 | $ 15 |
| U.S. federal statutory tax rate, Percent | 21.00% | 21.00% | 21.00% | 21.00% |
| State income taxes, net of federal income tax effect, Percent | 0.00% | 0.00% | 0.50% | 0.70% |
| Flow through related to deduction of meters and mixed service costs, Percent | (2.20%) | (1.50%) | (2.50%) | (3.50%) |
| Excess deferred tax amortization, Percent | (6.30%) | (6.50%) | (4.00%) | (5.10%) |
| Other, Percent | 0.00% | (6.50%) | (2.10%) | (2.20%) |
| Total other adjustments, Percent | (8.50%) | (14.50%) | (8.60%) | (10.80%) |
| Effective tax rate, Percent | 12.50% | 6.50% | 12.90% | 10.90% |
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- Definition Effective Income Tax Rate Reconciliation, Excess Deferred Tax Amortization, Amount. No definition available.
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- Definition Effective Income Tax Rate Reconciliation, Excess deferred tax amortization, Percent. No definition available.
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- Definition Effective income tax reconciliation flow through related to deduction of meters and mixed service cost. 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 reported income tax benefit (expense) from difference to income tax expense (benefit) computed by applying statutory federal (national) income tax rate to pretax income (loss) from continuing operation, attributable to other reconciling items. Excludes state and local income tax expense (benefit), federal tax expense (benefit), statutory income tax expense (benefit) outside of country of domicile, tax credit, nondeductible expense, deduction, income tax settlement, income tax contingency, and cross-border tax law. 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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- 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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- Definition Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operations attributable to deduction. Includes, but is not limited to, dividend deduction, deduction for dividend paid to employee stock ownership plan (ESOP), Medicare prescription drug benefit subsidy deduction, and other deductions. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- 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 difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying statutory federal (national) tax rate to pretax income (loss) from continuing operation attributable to other reconciling item. Excludes state and local income tax expense (benefit), federal tax expense (benefit), statutory income tax expense (benefit) outside of country of domicile, tax credit, nondeductible expense, deduction, income tax settlement, income tax contingency, and cross-border tax law. 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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- Definition Indicates tax jurisdiction of domicile. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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