Accelerated AMT Credit Refund Received Under CARES Act

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- Definition

Decrease to Recoverable Future Taxes Impact of Change in Corporate Tax Rate

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Amount of annual reduction to the corporate income tax rate.

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Income Taxes [Line Items]

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- Definition

Increase to Taxes Refundable to Customers Impact of Changes in Corporate Tax Rate

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- Definition

Regulatory assets representing future amounts collectible from customers corresponding to additional deferred income taxes not previously recorded because of ratemaking practices.

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- Definition

Reduction in Deferred Taxes Rate Regulated Activities Impact of Change in Corporate Tax Rate

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- Definition

Noncurrent regulatory liability representing the reduction of previously recorded deferred income taxes associated with rate-regulated activities that are expected to be refundable to customers as of the end of the period.

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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)
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Amount of income tax expense (benefit) from continuing operations attributable to an adjustment of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of unrecognized tax benefits.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	Sep. 30, 2032	Sep. 30, 2024	Sep. 30, 2022	Oct. 01, 2024	Sep. 30, 2021	Sep. 30, 2020
Income Taxes [Line Items]
Accelerated AMT Credit Refund Received Under CARES Act						$ 42,500
Taxes Refundable to Customers			$ 362,098		$ 354,089
Recoverable Future Taxes			106,247		121,992
Unrecognized Tax Benefits			0		0	$ 0
Pennsylvania [Member]
Income Taxes [Line Items]
Income Tax Benefit from Change in Enacted Tax Rate			(28,400)
Reduction in Deferred Taxes for Rate Regulated Activities Due to Remeasurement of Deferred Income Tax Assets and Liabilities			37,200
Pennsylvania [Member] \| Subsequent Event [Member]
Income Taxes [Line Items]
Corporate Income Tax Rate	4.99%	8.99%
Annual Reduction in Corporate Income Tax Rate from Fiscal 2025 to Fiscal 2032				0.50%
Pennsylvania [Member] \| Taxes Refundable To Customers [Member]
Income Taxes [Line Items]
Increase in Taxes Refundable to Customers Due to Changes in Corporate Tax Rate			17,400
Pennsylvania [Member] \| Recoverable Future Taxes [Member]
Income Taxes [Line Items]
Decrease to Recoverable Future Taxes Impact of Change in Corporate Tax Rate			19,800
Deferred Income Taxes [Member]
Income Taxes [Line Items]
Taxes Refundable to Customers			362,100		354,100
Recoverable Future Taxes			106,200		$ 122,000
Remaining State Deferred Tax Assets [Member]
Income Taxes [Line Items]
Reversal of Valuation Allowance			(24,900)
Pennsylvania Tax Rate Change [Member]
Income Taxes [Line Items]
Reversal of Valuation Allowance			(5,500)
Sale of California Assets [Member]
Income Taxes [Line Items]
Reversal of Valuation Allowance			$ (27,200)