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

+ References

No definition available.

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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

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-Publisher FASB
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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of investment in equity security without readily determinable fair value.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
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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, 2019 USD ($) mi	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)
Schedule of Equity Method Investments [Line Items]
Ownership interests in certain subsidiaries under equity method investment, maximum	100.00%
Investments	$ 242.4	$ 147.2
Equity method investments	189.6	87.6	$ 59.1
Pennant
Schedule of Equity Method Investments [Line Items]
Equity method investments	90.8
UGI PennEast, LLC \| PennEast
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 84.7	$ 72.6
Southern Company \| PennEast
Schedule of Equity Method Investments [Line Items]
Ownership percentage	20.00%
New Jersey Resources \| PennEast
Schedule of Equity Method Investments [Line Items]
Ownership percentage	20.00%
South Jersey Industries \| PennEast
Schedule of Equity Method Investments [Line Items]
Ownership percentage	20.00%
Enbridge Inc \| PennEast
Schedule of Equity Method Investments [Line Items]
Ownership percentage	20.00%
PennEast
Schedule of Equity Method Investments [Line Items]
Area of natural gas pipeline to be constructed (in miles) \| mi	120
Pipeline contract term	15 years
Affiliated Entity \| UGI PennEast, LLC \| PennEast
Schedule of Equity Method Investments [Line Items]
Ownership percentage	20.00%