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Differences Between Provisions for Income Taxes and Provisions Calculated at Statutory Federal Tax Rate (Detail) | 3 Months Ended
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Mar. 31, 2023 | Mar. 31, 2022
Income Tax Examination [Line Items] |  |
Statutory Federal Income Tax Rate | 21.00% | 21.00%
State Income Taxes, net | 6.00% | 6.00%
Utility Plant Differences | (1.00%) | (1.00%)
Effective Income Tax Rate | 26.00% | 26.00%

X
- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319 + Details
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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 -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 6.I.Fact.4) -URI https://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)(2)) -URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319 + Details
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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/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 6.I.Fact.4) -URI https://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319 + Details
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- Definition Effective income tax rate reconciliation domestic income tax rate differential. + References No definition available. + Details
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