Income Taxes - Differences Between Provisions for Income Taxes and Provisions Calculated at Statutory Federal Tax Rate (Detail)	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Tax Examination [Line Items]
Statutory Federal Income Tax Rate	21.00%	21.00%	21.00%
State Income Taxes, net	6.00%	6.00%	6.00%
Utility Plant Differences	(5.00%)	(5.00%)	(6.00%)
Other, net	1.00%	1.00%	0.00%
Effective Income Tax Rate	23.00%	23.00%	21.00%

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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-Name Accounting Standards Codification
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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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (b)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 231
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482663/740-10-55-231

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-Topic 235
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-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Subparagraph (e)
-Publisher FASB
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- Definition

Effective income tax rate reconciliation domestic income tax rate differential.

+ References

No definition available.

+ Details

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