Related Party Transactions (Details) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2019 USD ($) Bcf	Jun. 30, 2018 USD ($) Bcf	Jun. 30, 2019 USD ($) Bcf	Jun. 30, 2018 USD ($) Bcf	Sep. 30, 2018 USD ($) Bcf
Related Party Transaction
Related party costs incurred	$ 2,861	$ 4,325	$ 11,571	$ 10,780
UGI and Subsidiaries \| Administrative Services
Related Party Transaction
Amount of related party transaction	$ 1,536	$ 1,665	$ 4,228	$ 4,070
Energy Services
Related Party Transaction
Volume of gas storage inventory (in bcf of natural gas) \| Bcf	3.3	3.6	3.3	3.6	6.7
Natural gas storage inventory, related parties, current	$ 8,234	$ 9,294	$ 8,234	$ 9,294	$ 17,701
Revenue from related parties	10,041	11,582	$ 57,467	93,974
Term of agreements (in years)			1 year
Purchases from related party	16,568	19,429	$ 107,245	140,455
Energy Services \| SCAAs
Related Party Transaction
Amount of related party transaction	784	701	$ 2,303	2,127
SCAA contract term (in years)			3 years
Related party costs incurred	7,045	8,114	$ 10,314	11,394
Related party security deposits	7,640	11,040	7,640	11,040	$ 13,840
Energy Services \| Exclusive of Transactions Pursuant SCAAs
Related Party Transaction
Related party costs incurred	$ 3,222	$ 5,828	$ 93,579	$ 87,782

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