Related Party Transactions (Details) $ in Thousands	3 Months Ended
Dec. 31, 2018 USD ($) Bcf	Dec. 31, 2017 USD ($) Bcf	Sep. 30, 2018 USD ($) Bcf
Related Party Transaction
Related party costs incurred	$ 3,512	$ 2,689
UGI and Subsidiaries \| Administrative Services
Related Party Transaction
Amount of related party transaction	$ 1,182	$ 1,046
Energy Services
Related Party Transaction
Volume of gas storage inventory (in bcf of natural gas) \| Bcf	5.9	6.1	6.7
Natural gas storage inventory, related parties, current	$ 15,921	$ 17,043	$ 17,701
Revenue from related parties	$ 22,862	21,147
Term of agreements (in years)	1 year
Purchases from related party	$ 44,382	37,597
Energy Services \| SCAAs
Related Party Transaction
Amount of related party transaction	$ 743	718
SCAA contract term (in years)	3 years
Related party costs incurred	$ 3,101
Related party security deposits	9,040		$ 11,040
Energy Services \| Exclusive of Transactions Pursuant SCAAs
Related Party Transaction
Related party costs incurred	$ 36,237	$ 34,588

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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