Equity Method Investments (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
Jun. 30, 2024	Jun. 30, 2024	Sep. 30, 2024	Jun. 30, 2025
Schedule of Equity Method Investments [Line Items]
Carrying Value	$ 349	$ 349	$ 370	$ 392
Other
Schedule of Equity Method Investments [Line Items]
Carrying Value	0	0	1	1
Midstream & Marketing
Schedule of Equity Method Investments [Line Items]
Carrying Value	339	339	359	387
Acquisition and integration expenses associated with the CMG Acquisition	0	0
Midstream & Marketing \| Aurum Renewables
Schedule of Equity Method Investments [Line Items]
Carrying Value	$ 46	$ 46	$ 47	$ 46
Ownership Interest	40.00%	40.00%	40.00%	40.00%
Midstream & Marketing \| Pine Run
Schedule of Equity Method Investments [Line Items]
Carrying Value	$ 83	$ 83	$ 86	$ 96
Ownership Interest	49.00%	49.00%	49.00%	49.00%
Midstream & Marketing \| MBL Bioenergy
Schedule of Equity Method Investments [Line Items]
Carrying Value	$ 190	$ 190	$ 206	$ 222
Ownership Interest	99.99%	99.99%	99.99%	99.99%
Midstream & Marketing \| Other
Schedule of Equity Method Investments [Line Items]
Carrying Value	$ 20	$ 20	$ 20	$ 23
UGI International
Schedule of Equity Method Investments [Line Items]
Carrying Value	$ 10	$ 10	10	$ 4
UGI International \| Joint Venture
Schedule of Equity Method Investments [Line Items]
Acquisition and integration expenses associated with the CMG Acquisition			$ 25

Amount of other-than-temporary decline in value that has been recognized against investment accounted for under equity method of accounting.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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