Nature of Operations (Details) $ in Millions	6 Months Ended
Mar. 31, 2018 USD ($) county	Mar. 31, 2017 USD ($)
Investment [Line Items]
General Partner incentive distribution \| $	$ 22.7	$ 20.9
Number of counties of operation \| county	1
Amerigas Propane \| AmeriGas Partners
Investment [Line Items]
General Partner held a general partner interest in AmeriGas Partners	1.00%
Percentage of limited partnership interest in AmeriGas Partners	25.30%
General public as limited partner interests in AmeriGas Partners	73.70%
Amerigas Propane \| AmeriGas OLP
Investment [Line Items]
Effective ownership interest in AmeriGas OLP	27.00%

Line items represent reporting 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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 12
-Sentence Column A

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

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