Related Party Transactions (Details) $ in Thousands	12 Months Ended
Sep. 30, 2017 USD ($) agreement Bcf	Sep. 30, 2016 USD ($) Bcf	Sep. 30, 2015 USD ($)
Related Party Transaction
Related party costs incurred	$ 12,354	$ 11,863	$ 11,956
UGI and Subsidiaries \| Administrative Services
Related Party Transaction
Amount of related party transaction	$ 4,346	$ 5,069	3,168
Energy Services
Related Party Transaction
Agreement term (in years)	1 year
Volume of gas storage inventory (in bcf of natural gas) \| Bcf	6.8	4.6
Natural gas storage inventory, related parties, current	$ 19,323	$ 11,148
Revenue from related parties	50,948	30,743	79,182
Purchases from related party	84,402	35,067	85,383
Energy Services \| SCAAs
Related Party Transaction
Amount of related party transaction	$ 2,747	2,002	2,339
Agreement term (in years)	3 years
Number of storage agreements \| agreement	4
Related party costs incurred	$ 21,424	12,739	16,849
Related party security deposits	11,040	8,100
Energy Services \| Exclusive of Transactions Pursuant SCAAs
Related Party Transaction
Related party costs incurred	$ 76,010	$ 63,331	$ 47,794

Natural Gas Storage Inventory, Related Parties, Current

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Amount of deposits held by the entity for a related party (entity, shareholder, employee).

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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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