Revenue from Contracts with Customers - Schedule of Disaggregated Revenues By Reportable Segment (Details) - USD ($) $ in Millions		12 Months Ended
	Nov. 01, 2022	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		$ 8,761	$ 9,981	$ 7,348
Other revenues		167	125	99
Total revenues		8,928	10,106	7,447
Weather Normalization Adjustment Rider | Pennsylvania Public Utility Commission | Regulated natural gas utilities
Disaggregation of Revenue [Line Items]
Public utilities, rate period	5 years
Total Utility
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		1,742	1,510	1,006
Residential
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		1,020	875	568
Commercial & Industrial
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		413	365	218
Large delivery service
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		177	171	148
Off-system sales and capacity releases
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		89	76	51
Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		43	23	21
Total Non-Utility
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		7,019	8,471	6,342
Retail
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		3,952	4,436	3,957
Wholesale
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		325	496	328
Energy Marketing
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		2,139	2,951	1,564
Pipeline
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		251	211	181
Peaking
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		31	48	16
Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		14	9	8
Electricity Generation
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		33	34	13
Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		274	286	275
Elim- inations
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		(323)	(474)	(288)
Other revenues		(3)	(3)	(3)
Total revenues		(326)	(477)	(291)
Elim- inations | Total Utility
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		(74)	(105)	(64)
Elim- inations | Residential
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Elim- inations | Commercial & Industrial
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Elim- inations | Large delivery service
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Elim- inations | Off-system sales and capacity releases
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		(73)	(104)	(62)
Elim- inations | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		(1)	(1)	(2)
Elim- inations | Total Non-Utility
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		(249)	(369)	(224)
Elim- inations | Retail
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Elim- inations | Wholesale
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Elim- inations | Energy Marketing
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		(143)	(264)	(126)
Elim- inations | Pipeline
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Elim- inations | Peaking
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		(106)	(105)	(98)
Elim- inations | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Elim- inations | Electricity Generation
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Elim- inations | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Elim- inations | AmeriGas Propane
Disaggregation of Revenue [Line Items]
Total revenues		0	0	0
Elim- inations | UGI International
Disaggregation of Revenue [Line Items]
Total revenues		0	0	0
Elim- inations | Midstream & Marketing
Disaggregation of Revenue [Line Items]
Total revenues		251	369	224
Elim- inations | Utilities
Disaggregation of Revenue [Line Items]
Total revenues		74	105	64
Operating Segments | AmeriGas Propane
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		2,496	2,864	2,548
Other revenues		85	79	66
Total revenues		2,581	2,943	2,614
Operating Segments | AmeriGas Propane | Total Utility
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | AmeriGas Propane | Residential
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | AmeriGas Propane | Commercial & Industrial
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | AmeriGas Propane | Large delivery service
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | AmeriGas Propane | Off-system sales and capacity releases
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | AmeriGas Propane | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | AmeriGas Propane | Total Non-Utility
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		2,496	2,864	2,548
Operating Segments | AmeriGas Propane | Retail
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		2,184	2,439	2,203
Operating Segments | AmeriGas Propane | Wholesale
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		118	218	139
Operating Segments | AmeriGas Propane | Energy Marketing
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | AmeriGas Propane | Pipeline
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | AmeriGas Propane | Peaking
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | AmeriGas Propane | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | AmeriGas Propane | Electricity Generation
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | AmeriGas Propane | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		194	207	206
Operating Segments | UGI International
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		2,927	3,652	2,617
Other revenues		38	34	34
Total revenues		2,965	3,686	2,651
Operating Segments | UGI International | Total Utility
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | UGI International | Residential
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | UGI International | Commercial & Industrial
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | UGI International | Large delivery service
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | UGI International | Off-system sales and capacity releases
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | UGI International | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | UGI International | Total Non-Utility
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		2,927	3,652	2,617
Operating Segments | UGI International | Retail
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		1,768	1,997	1,754
Operating Segments | UGI International | Wholesale
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		207	278	189
Operating Segments | UGI International | Energy Marketing
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		872	1,298	605
Operating Segments | UGI International | Pipeline
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | UGI International | Peaking
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | UGI International | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | UGI International | Electricity Generation
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | UGI International | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		80	79	69
Operating Segments | Midstream & Marketing
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		1,845	2,324	1,401
Other revenues		2	2	5
Total revenues		1,847	2,326	1,406
Operating Segments | Midstream & Marketing | Total Utility
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | Midstream & Marketing | Residential
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | Midstream & Marketing | Commercial & Industrial
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | Midstream & Marketing | Large delivery service
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | Midstream & Marketing | Off-system sales and capacity releases
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | Midstream & Marketing | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | Midstream & Marketing | Total Non-Utility
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		1,845	2,324	1,401
Operating Segments | Midstream & Marketing | Retail
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | Midstream & Marketing | Wholesale
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | Midstream & Marketing | Energy Marketing
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		1,410	1,917	1,085
Operating Segments | Midstream & Marketing | Pipeline
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		251	211	181
Operating Segments | Midstream & Marketing | Peaking
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		137	153	114
Operating Segments | Midstream & Marketing | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		14	9	8
Operating Segments | Midstream & Marketing | Electricity Generation
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		33	34	13
Operating Segments | Midstream & Marketing | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | Utilities
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		1,816	1,615	1,070
Other revenues		38	5	9
Total revenues		1,854	1,620	1,079
Operating Segments | Utilities | Total Utility
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		1,816	1,615	1,070
Operating Segments | Utilities | Residential
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		1,020	875	568
Operating Segments | Utilities | Commercial & Industrial
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		413	365	218
Operating Segments | Utilities | Large delivery service
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		177	171	148
Operating Segments | Utilities | Off-system sales and capacity releases
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		162	180	113
Operating Segments | Utilities | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		44	24	23
Operating Segments | Utilities | Total Non-Utility
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | Utilities | Retail
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | Utilities | Wholesale
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | Utilities | Energy Marketing
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | Utilities | Pipeline
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | Utilities | Peaking
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | Utilities | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | Utilities | Electricity Generation
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Operating Segments | Utilities | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Corporate & Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Other revenues		7	8	(12)
Total revenues		7	8	(12)
Corporate & Other | Total Utility
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Corporate & Other | Residential
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Corporate & Other | Commercial & Industrial
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Corporate & Other | Large delivery service
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Corporate & Other | Off-system sales and capacity releases
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Corporate & Other | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Corporate & Other | Total Non-Utility
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Corporate & Other | Retail
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Corporate & Other | Wholesale
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Corporate & Other | Energy Marketing
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Corporate & Other | Pipeline
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Corporate & Other | Peaking
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Corporate & Other | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Corporate & Other | Electricity Generation
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		0	0	0
Corporate & Other | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers		$ 0	$ 0	$ 0