Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2022	Sep. 30, 2021
Debt Instrument [Line Items]
Total long-term debt	$ 6,632	$ 6,449
Less: current maturities	(149)	(110)
Total long-term debt due after one year	6,483	6,339
AmeriGas Propane
Debt Instrument [Line Items]
Unamortized debt issuance costs	(12)	(16)
Total long-term debt	2,563	2,560
AmeriGas Propane \| Other
Debt Instrument [Line Items]
Long-term debt, gross	$ 0	1
AmeriGas Propane \| Senior Notes \| 5.50% due May 2025
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	5.50%
Long-term debt, gross	$ 700	700
AmeriGas Propane \| Senior Notes \| 5.875% due August 2026
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	5.875%
Long-term debt, gross	$ 675	675
AmeriGas Propane \| Senior Notes \| 5.625% due May 2024
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	5.625%
Long-term debt, gross	$ 675	675
AmeriGas Propane \| Senior Notes \| 5.75% due May 2027
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	5.75%
Long-term debt, gross	$ 525	525
UGI International
Debt Instrument [Line Items]
Unamortized debt issuance costs	(6)	(5)
Total long-term debt	$ 682	770
UGI International \| Senior Notes \| 3.25% Senior Notes due November 2025
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	3.25%
Long-term debt, gross	$ 0	405
UGI International \| Senior Notes \| 2.50% Senior Notes due December 2029
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	2.50%
Long-term debt, gross	$ 392	0
UGI International \| Other \| Other
Debt Instrument [Line Items]
Long-term debt, gross	2	23
UGI International \| Term Loan \| Variable-rate term loan
Debt Instrument [Line Items]
Long-term debt, gross	294	347
Midstream & Marketing
Debt Instrument [Line Items]
Unamortized debt issuance costs	(7)	(10)
Total long-term debt	710	716
Midstream & Marketing \| Other \| Other
Debt Instrument [Line Items]
Long-term debt, gross	40	42
Midstream & Marketing \| Term Loan \| Variable-rate term loan
Debt Instrument [Line Items]
Long-term debt, gross	677	684
Utilities
Debt Instrument [Line Items]
Unamortized debt issuance costs	(6)	(6)
Total long-term debt	1,656	1,451
Utilities \| Mountaineer senior notes
Debt Instrument [Line Items]
Long-term debt, gross	$ 201	164
Utilities \| Senior Notes \| 4.12% due September 2046
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	4.12%
Long-term debt, gross	$ 200	200
Utilities \| Senior Notes \| 4.98% due March 2044
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	4.98%
Long-term debt, gross	$ 175	175
Utilities \| Senior Notes \| 3.12% due April 2050
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	3.12%
Long-term debt, gross	$ 150	150
Utilities \| Senior Notes \| 4.55% due February 2049
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	4.55%
Long-term debt, gross	$ 150	150
Utilities \| Senior Notes \| 4.12% due October 2046
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	4.12%
Long-term debt, gross	$ 100	100
Utilities \| Senior Notes \| 6.21% due September 2036
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	6.21%
Long-term debt, gross	$ 100	100
Utilities \| Senior Notes \| 2.95% due June 2026
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	2.95%
Long-term debt, gross	$ 100	100
Utilities \| Senior Notes \| 1.59% due June 2026
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	1.59%
Long-term debt, gross	$ 100	100
Utilities \| Senior Notes \| 1.64% due September 2026
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	1.64%
Long-term debt, gross	$ 75	75
Utilities \| Senior Notes \| 4.75% due July 2032
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	4.75%
Long-term debt, gross	$ 90	0
Utilities \| Senior Notes \| 4.99% due September 2052
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	4.99%
Long-term debt, gross	$ 85	0
Utilities \| Other \| Other
Debt Instrument [Line Items]
Long-term debt, gross	1	1
Utilities \| Term Loan \| Variable-rate term loan
Debt Instrument [Line Items]
Long-term debt, gross	$ 95	102
Utilities \| Medium-term Notes \| 6.13% due October 2034
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	6.13%
Long-term debt, gross	$ 20	20
Utilities \| Medium-term Notes \| 6.50% due August 2033
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	6.50%
Long-term debt, gross	$ 20	20
UGI Corporation
Debt Instrument [Line Items]
Unamortized debt issuance costs	(2)	(5)
Total long-term debt	1,015	945
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	250	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	252	185
Other
Debt Instrument [Line Items]
Total long-term debt	$ 6	$ 7

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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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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

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