SCHEDULE I — CONDENSED FINANCIAL INFORMATION OF REGISTRANT (PARENT COMPANY) - STATEMENTS OF INCOME (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Condensed Financial Statements, Captions [Line Items]
Revenues	$ 7,447	$ 6,559	$ 7,320
Costs and expenses:
Operating and administrative expenses	2,014	1,911	1,963
Other operating income, net	33	21	31
Total costs and expenses	5,097	5,577	6,703
Operating income	2,350	982	617
Pension and other postretirement plans non-service expense	1	0	1
Income tax expense (benefit)	522	135	93
Equity in income of unconsolidated subsidiaries	(63)	27	9
Net income attributable to UGI Corporation	1,467	532	256
Comprehensive income attributable to UGI Corporation	$ 1,474	$ 602	$ 156
Earnings per common share attributable to UGI Corporation stockholders:
Basic (in dollars per share)	$ 7.02	$ 2.55	$ 1.44
Diluted (in dollars per share)	$ 6.92	$ 2.54	$ 1.41
Weighted - average common shares outstanding (thousands):
Basic (in shares)	209,063	208,928	178,417
Diluted (in shares)	212,126	209,869	181,111
Parent Company
Condensed Financial Statements, Captions [Line Items]
Revenues	$ 0	$ 0	$ 0
Costs and expenses:
Operating and administrative expenses	94	56	50
Other operating income, net	(65)	(54)	(50)
Total costs and expenses	29	2	0
Operating income	(29)	(2)	0
Pension and other postretirement plans non-service expense	0	0	(1)
Interest expense	(27)	(32)	(6)
Loss before income taxes	(56)	(34)	(7)
Income tax expense (benefit)	9	17	(3)
Loss before equity in income of unconsolidated subsidiaries	(65)	(51)	(4)
Equity in income of unconsolidated subsidiaries	1,532	583	260
Net income attributable to UGI Corporation	1,467	532	256
Other comprehensive income (loss)	7	(12)	(3)
Equity in other comprehensive income (loss) of unconsolidated subsidiaries	0	82	(97)
Comprehensive income attributable to UGI Corporation	$ 1,474	$ 602	$ 156
Earnings per common share attributable to UGI Corporation stockholders:
Basic (in dollars per share)	$ 7.02	$ 2.55	$ 1.44
Diluted (in dollars per share)	$ 6.92	$ 2.54	$ 1.41
Weighted - average common shares outstanding (thousands):
Basic (in shares)	209,063	208,928	178,417
Diluted (in shares)	212,126	209,869	181,111