Income Taxes - Differences Between Provisions for Income Taxes and Provisions Calculated at Statutory Federal Tax Rate (Detail) - USD ($) $ in Thousands |
6 Months Ended | 12 Months Ended | |
|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Dec. 31, 2017 |
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| Income Tax Examination [Line Items] | |||
| U.S. Federal Statutory Tax Rate | $ 10,695 | ||
| U.S. Federal Statutory Tax Rate Percent | 21.00% | 21.00% | 21.00% |
| Tax Jurisdiction Of Domicile Extensible Enumeration | us-gaap:ForeignCountryMember | ||
| State Income Taxes, net of Federal Income Tax | $ 3,323 | ||
| State Income Taxes, net | 6.50% | 7.00% | |
| Production Tax Credit | $ (98) | ||
| Production Tax Credit Percent | (0.20%) | ||
| Regulatory Amortization of Excess ADIT | $ (1,167) | ||
| Regulatory Amortization of Excess ADIT Percent | (2.30%) | ||
| Utility Plant Differences | (4.00%) | ||
| Other | $ 230 | ||
| Other, net | 0.50% | ||
| Effective Income Tax Continuing Operations Amount | $ 12,983 | ||
| Effective Income Tax Rate | 25.50% | 24.00% | |
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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 amortization. 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 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 tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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- 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 nondeductible amortization. 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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| 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 tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Indicates tax jurisdiction of domicile. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Effective Income Tax Continuing Operations Amount No definition available.
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- Definition Effective income tax rate reconciliation domestic income tax rate differential. No definition available.
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