Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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-Section 50
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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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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Revenue from Contracts with Customers - Narrative (Details) - USD ($) $ in Millions	6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Contract with customer, liability, current	$ 62.2	$ 60.4	$ 114.1
Contract with customer, liability, revenue recognized	82.2	$ 82.8
Midstream and Marketing
Disaggregation of Revenue [Line Items]
Revenue, remaining performance obligation	2,000.0
UGI Utilities
Disaggregation of Revenue [Line Items]
Revenue, remaining performance obligation	$ 200.0