Income Tax Expense (Benefit), Accelerated Depreciation

No definition available.

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- Definition

Net Operating Loss Carryback

+ References

No definition available.

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- Definition

Tax Cuts And Jobs Act of 2017, Transition Tax For Accumulated Foreign Earnings, Provisional Income Tax Expense (Benefit)

+ References

No definition available.

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

+ References

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible foreign tax credit carryforwards.

+ References

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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

No definition available.

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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 foreign tax credit.

+ References

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- Definition

Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

+ References

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

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- Definition

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

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Income Taxes - Narrative (Details) - USD ($)	12 Months Ended
Income Taxes - Narrative (Details) - USD ($)	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Income Tax Examination [Line Items]
Foreign tax credits	$ 0	$ 0	$ 10,000,000
Foreign tax credit carryforwards	79,000,000	81,000,000
Net operating loss carryback	15,000,000	32,000,000
Income taxes receivable	128,000,000	80,000,000
Tax Cuts And Jobs Act of 2017, transition tax for accumulated foreign earnings, provisional Income tax expense (benefit)	8,000,000	0	2,000,000
Deferred tax assets relating to operating loss carryforwards	53,000,000	34,000,000
Increase (decrease) in valuation allowance	33,000,000	(14,000,000)
Unrecognized tax benefits if recognized would impact the reported effective tax rate	4,000,000	4,000,000	11,000,000
Future capital losses from PennEast and Hudson investments
Income Tax Examination [Line Items]
Increase (decrease) in valuation allowance	30,000,000
Future FTC's realizable
Income Tax Examination [Line Items]
Increase (decrease) in valuation allowance	(10,000,000)
Notional interest deduction carryover
Income Tax Examination [Line Items]
Increase (decrease) in valuation allowance	10,000,000	16,000,000
AmeriGas Propane
Income Tax Examination [Line Items]
Operating loss carryforwards	7,000,000
Other Subsidiaries
Income Tax Examination [Line Items]
Deferred tax assets relating to operating loss carryforwards	52,000,000
Fiscal 2020 carryback to Fiscal 2015
Income Tax Examination [Line Items]
Income taxes receivable		90,000,000
Fiscal 2021 carryback to Fiscal 2016
Income Tax Examination [Line Items]
Income taxes receivable	38,000,000
Foreign \| Flaga
Income Tax Examination [Line Items]
Operating loss carryforwards	10,000,000
Foreign \| UGI France
Income Tax Examination [Line Items]
Operating loss carryforwards	19,000,000
Foreign \| Italy
Income Tax Examination [Line Items]
Foreign tax credit carryforwards	23,000,000
Foreign \| Netherlands
Income Tax Examination [Line Items]
Operating loss carryforwards	5,000,000
State
Income Tax Examination [Line Items]
Decrease in income tax expense due to state tax flow through of accelerated depreciation	9,000,000	$ 11,000,000	$ 7,000,000
Operating loss carryforwards	606,000,000
Domestic \| Mountaintop Energy Holding, LLC
Income Tax Examination [Line Items]
Operating loss carryforwards	$ 24,000,000