Area Of Property To Be Constructed

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- Definition

Ownership interests in certain subsidiaries under equity method investment, maximum

+ References

No definition available.

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- Definition

Term Of Contract

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- References

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66022249&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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.

+ References

No definition available.

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Summary of Significant Accounting Policies - Principles of Consolidation (Details) $ in Millions	12 Months Ended
	Sep. 30, 2017 USD ($) mi	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)
Accounting Policies [Abstract]
Ownership interests in certain subsidiaries under equity method investment, maximum	100.00%
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 59.1	$ 25.9	$ 16.2
UGI PennEast, LLC \| PennEast
Schedule of Equity Method Investments [Line Items]
Ownership percentage	20.00%
Equity method investments	$ 51.0	$ 17.4
PennEast
Schedule of Equity Method Investments [Line Items]
Area of natural gas pipeline to be constructed (in miles) \| mi	118
Pipeline contract term	15 years