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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Business Acquisition, Equity Interest Issued Or Issuable, Conversion Of General Partner Interest, Number Of Shares

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
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Amount of incentive obligation paid in cash or stock during the period to a limited liability corporation managing member or limited partnership general partner.

+ 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)
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Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

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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)
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Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

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Nature of Operations (Details) $ / shares in Units, $ in Millions		6 Months Ended
	Mar. 31, 2019	Sep. 30, 2019 USD ($) $ / shares shares	Mar. 31, 2019 USD ($) county	Mar. 31, 2018 USD ($)
Investment [Line Items]
General Partner incentive distribution \| $			$ 22.9	$ 22.7
Number of counties of operation \| county			1
AmeriGas Propane \| AmeriGas Partners
Investment [Line Items]
General Partner held a general partner interest in AmeriGas Partners (percentage)	1.00%		1.00%
Percentage of limited partnership interest in AmeriGas Partners (percentage)	25.30%
General public as limited partner interests in AmeriGas Partners (percentage)	73.70%		73.70%
AmeriGas Propane \| AmeriGas OLP
Investment [Line Items]
Effective ownership interest in AmeriGas OLP (percentage)	27.00%		27.00%
Subsequent Event \| Merger Sub \| Forecast
Investment [Line Items]
Proposed consideration \| $		$ 530.0
Common Stock \| Subsequent Event \| Merger Sub \| Forecast
Investment [Line Items]
Proposed consideration issuable (in shares)		34,600,000
Units issuable (in units)		10,615,711
Proposed Consideration One \| Common Stock \| Subsequent Event \| Merger Sub \| Forecast
Investment [Line Items]
Number of shares issuable per acquiree stock (in shares)		0.6378
Proposed Consideration Two \| Common Stock \| Subsequent Event \| Merger Sub \| Forecast
Investment [Line Items]
Number of shares issuable per acquiree stock (in shares)		0.500
Proposed Consideration Two \| Cash Without Interest \| Subsequent Event \| Merger Sub \| Forecast
Investment [Line Items]
Cash issuable per acquiree stock \| $ / shares		$ 7.63
Proposed Consideration Three \| Cash Without Interest \| Subsequent Event \| Merger Sub \| Forecast
Investment [Line Items]
Cash issuable per acquiree stock \| $ / shares		$ 35.325