Related Party Transactions (Details) $ in Thousands	12 Months Ended
Sep. 30, 2018 USD ($) agreement Bcf	Sep. 30, 2017 USD ($) Bcf	Sep. 30, 2016 USD ($)
Related Party Transaction
Related party costs incurred	$ 14,234	$ 12,354	$ 11,863
UGI and Subsidiaries \| Administrative Services
Related Party Transaction
Amount of related party transaction	$ 5,305	$ 4,346	5,069
Energy Services
Related Party Transaction
Agreement term (in years)	1 year
Volume of gas storage inventory (in bcf of natural gas) \| Bcf	6.7	6.8
Natural gas storage inventory, related parties, current	$ 17,701	$ 19,323
Revenue from related parties	103,667	50,948	30,743
Purchases from related party	156,794	84,402	35,067
Energy Services \| SCAAs
Related Party Transaction
Amount of related party transaction	$ 2,824	2,747	2,002
Agreement term (in years)	3 years
Number of storage agreements \| agreement	4
Related party costs incurred	$ 19,854	21,424	12,739
Related party security deposits	11,040
Energy Services \| Exclusive of Transactions Pursuant SCAAs
Related Party Transaction
Related party costs incurred	$ 93,577	$ 76,010	$ 63,331

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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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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