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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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Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2021	May 07, 2021	Sep. 30, 2020
Debt Instrument [Line Items]
Total long-term debt	$ 6,449		$ 6,034
Less: current maturities	(110)		(53)
Total long-term debt due after one year	6,339		5,981
AmeriGas Propane
Debt Instrument [Line Items]
Unamortized debt issuance costs	(16)		(20)
Total long-term debt	2,560		2,560
AmeriGas Propane \| Other
Debt Instrument [Line Items]
Long-term debt, gross	$ 1		5
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	(5)		(7)
Total long-term debt	$ 770		778
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	$ 405		410
UGI International \| Term Loan \| Variable-rate term loan
Debt Instrument [Line Items]
Long-term debt, gross	347		352
Other
Debt Instrument [Line Items]
Total long-term debt	7		8
Other \| Other \| Other
Debt Instrument [Line Items]
Long-term debt, gross	23		23
Midstream & Marketing
Debt Instrument [Line Items]
Unamortized debt issuance costs	(10)		(12)
Total long-term debt	716		720
Midstream & Marketing \| Other \| Other
Debt Instrument [Line Items]
Long-term debt, gross	42		41
Midstream & Marketing \| Term Loan \| Variable-rate term loan
Debt Instrument [Line Items]
Long-term debt, gross	684		691
UGI Utilities
Debt Instrument [Line Items]
Unamortized debt issuance costs	(6)		(5)
Total long-term debt	1,451		1,121
UGI Utilities \| Mountaineer senior notes
Debt Instrument [Line Items]
Long-term debt, gross	$ 164		0
UGI 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
UGI 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
UGI 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
UGI 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
UGI 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
UGI 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
UGI 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
UGI Utilities \| Senior Notes \| 1.59% due June 2026
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	1.59%	1.59%
Long-term debt, gross	$ 100		0
UGI Utilities \| Senior Notes \| 1.64% due September 2026
Debt Instrument [Line Items]
Stated interest rate (as a percentage)	1.64%	1.64%
Long-term debt, gross	$ 75		0
UGI Utilities \| Other \| Other
Debt Instrument [Line Items]
Long-term debt, gross	1		3
UGI Utilities \| Term Loan \| Variable-rate term loan
Debt Instrument [Line Items]
Long-term debt, gross	$ 102		108
UGI 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
UGI 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	(5)		(3)
Total long-term debt	945		847
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		0
UGI Corporation \| Line of Credit
Debt Instrument [Line Items]
Long-term debt, gross	$ 185		$ 300