Common Stock and Equity-Based Compensation - Schedule of Payment for UGI Performance Unit and UGI Stock Unit Awards in Shares and Cash (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
UGI Performance Units
Share-based Compensation Arrangement by Share-based Payment Award
Number of original awards granted (in shares)	144,521	136,621	178,450
Performance period beginning January 1:	2016	2015	2014
Payment of awards:
Shares of UGI Common Stock issued, net of shares withheld for taxes	116,950	69,680	138,985
Cash paid	$ 9.9	$ 1.6	$ 10.9
UGI Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Number of original awards granted (in shares)	50,985	39,680	43,699
Payment of awards:
Shares of UGI Common Stock issued, net of shares withheld for taxes	43,479	29,095	15,990
Cash paid	$ 1.0	$ 0.6	$ 0.3

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- Definition

Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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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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Number of shares issued under share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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