Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2023	Sep. 30, 2022
Debt Instrument [Line Items]
Total long-term debt	$ 6,600	$ 6,632
Less: current maturities	(57)	(149)
Total long-term debt due after one year	6,543	6,483
AmeriGas Propane
Debt Instrument [Line Items]
Unamortized debt issuance costs	(15)	(12)
Total long-term debt	$ 2,385	2,563
AmeriGas Propane \| UGI Utilities Senior Notes: \| 5.50% due May 2025
Debt Instrument [Line Items]
Interest rate	5.50%
Long-term debt, gross	$ 700	700
AmeriGas Propane \| UGI Utilities Senior Notes: \| 5.875% due August 2026
Debt Instrument [Line Items]
Interest rate	5.875%
Long-term debt, gross	$ 675	675
AmeriGas Propane \| UGI Utilities Senior Notes: \| 5.625% due May 2024
Debt Instrument [Line Items]
Interest rate	5.625%
Long-term debt, gross	$ 0	675
AmeriGas Propane \| UGI Utilities Senior Notes: \| 5.75% due May 2027
Debt Instrument [Line Items]
Interest rate	5.75%
Long-term debt, gross	$ 525	525
AmeriGas Propane \| UGI Utilities Senior Notes: \| 9.375% due May 2028
Debt Instrument [Line Items]
Interest rate	9.375%
Long-term debt, gross	$ 500	0
UGI International
Debt Instrument [Line Items]
Unamortized debt issuance costs	(8)	(6)
Total long-term debt	$ 739	682
UGI International \| UGI Utilities Senior Notes: \| 2.50% Senior Notes due December 2029
Debt Instrument [Line Items]
Interest rate	2.50%
Long-term debt, gross	$ 424	392
UGI International \| Other \| Other
Debt Instrument [Line Items]
Long-term debt, gross	6	2
UGI International \| Term Loan Due March 2028 \| Variable-rate term loan
Debt Instrument [Line Items]
Long-term debt, gross	317	0
UGI International \| Term Loan Due October 2023 \| Variable-rate term loan
Debt Instrument [Line Items]
Long-term debt, gross	0	294
Midstream & Marketing
Debt Instrument [Line Items]
Unamortized debt issuance costs	(15)	(7)
Total long-term debt	820	710
Midstream & Marketing \| Other \| Other
Debt Instrument [Line Items]
Long-term debt, gross	41	40
Midstream & Marketing \| Term Loan \| Variable-rate term loan
Debt Instrument [Line Items]
Long-term debt, gross	794	677
Utilities
Debt Instrument [Line Items]
Unamortized debt issuance costs	(6)	(6)
Total long-term debt	1,649	1,656
Utilities \| Mountaineer senior notes
Debt Instrument [Line Items]
Long-term debt, gross	$ 199	201
Utilities \| UGI Utilities Senior Notes: \| 4.12% due September 2046
Debt Instrument [Line Items]
Interest rate	4.12%
Long-term debt, gross	$ 200	200
Utilities \| UGI Utilities Senior Notes: \| 4.98% due March 2044
Debt Instrument [Line Items]
Interest rate	4.98%
Long-term debt, gross	$ 175	175
Utilities \| UGI Utilities Senior Notes: \| 3.12% due April 2050
Debt Instrument [Line Items]
Interest rate	3.12%
Long-term debt, gross	$ 150	150
Utilities \| UGI Utilities Senior Notes: \| 4.55% due February 2049
Debt Instrument [Line Items]
Interest rate	4.55%
Long-term debt, gross	$ 150	150
Utilities \| UGI Utilities Senior Notes: \| 4.12% due October 2046
Debt Instrument [Line Items]
Interest rate	4.12%
Long-term debt, gross	$ 100	100
Utilities \| UGI Utilities Senior Notes: \| 6.21% due September 2036
Debt Instrument [Line Items]
Interest rate	6.21%
Long-term debt, gross	$ 100	100
Utilities \| UGI Utilities Senior Notes: \| 2.95% due June 2026
Debt Instrument [Line Items]
Interest rate	2.95%
Long-term debt, gross	$ 100	100
Utilities \| UGI Utilities Senior Notes: \| 1.59% due June 2026
Debt Instrument [Line Items]
Interest rate	1.59%
Long-term debt, gross	$ 100	100
Utilities \| UGI Utilities Senior Notes: \| 1.64% due September 2026
Debt Instrument [Line Items]
Interest rate	1.64%
Long-term debt, gross	$ 75	75
Utilities \| UGI Utilities Senior Notes: \| 4.75% due July 2032
Debt Instrument [Line Items]
Interest rate	4.75%
Long-term debt, gross	$ 90	90
Utilities \| UGI Utilities Senior Notes: \| 4.99% due September 2052
Debt Instrument [Line Items]
Interest rate	4.99%
Long-term debt, gross	$ 85	85
Utilities \| Other \| Other
Debt Instrument [Line Items]
Long-term debt, gross	2	1
Utilities \| Term Loan \| Variable-rate term loan
Debt Instrument [Line Items]
Long-term debt, gross	$ 89	95
Utilities \| UGI Utilities Medium-Term Notes: \| 6.13% due October 2034
Debt Instrument [Line Items]
Interest rate	6.13%
Long-term debt, gross	$ 20	20
Utilities \| UGI Utilities Medium-Term Notes: \| 6.50% due August 2033
Debt Instrument [Line Items]
Interest rate	6.50%
Long-term debt, gross	$ 20	20
UGI Corporation
Debt Instrument [Line Items]
Unamortized debt issuance costs	(3)	(2)
Total long-term debt	1,007	1,015
UGI Corporation \| Term Loan \| 3-year Term loan
Debt Instrument [Line Items]
Long-term debt, gross	300	300
UGI Corporation \| Term Loan \| 5-year Term Loan
Debt Instrument [Line Items]
Long-term debt, gross	212	250
UGI Corporation \| Term Loan \| 7-Year Term Loan
Debt Instrument [Line Items]
Long-term debt, gross	215	215
UGI Corporation \| Line of Credit
Debt Instrument [Line Items]
Long-term debt, gross	283	252
Other
Debt Instrument [Line Items]
Total long-term debt	$ 0	$ 6

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as current. Excludes lease obligation.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

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