Decrease To Recoverable Future Taxes Impact of Change In Corporate 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

Reduction In Deferred Taxes Rate Regulated Activities Impact Of Change In Corporate Tax Rate

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- Definition

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

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

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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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Carrying amount as of the balance sheet date of income taxes previously overpaid to tax authorities (such as U.S. Federal, state and local tax authorities) representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Also called income tax refund receivable.

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Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
Income Taxes (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2018	Sep. 30, 2017
Income Taxes [Line Items]
Effective Tax Rate	24.90%	23.30%	22.30%	(7.20%)
Federal Statutory Rate			21.00%		24.50%	35.00%
Reduction to Income Tax Expense Due to Remeasurement of Deferred Income Tax Assets and Liabilities			$ 5,000		$ 103,500
Reduction In Deferred Taxes for Rate Regulated Activities Due to Remeasurement of Deferred Income Tax Assets and Liabilities					336,700
Decrease to Recoverable Future Taxes Due to Change in Corporate Tax Rate					65,700
Increase in Taxes Refundable to Customers Due to Change in Corporate Tax Rate					271,000
Federal [Member] \| Other Noncurrent Assets [Member]
Income Taxes [Line Items]
Income Taxes Receivable	$ 42,546		$ 42,546		$ 0