Related Party Transactions (Details) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2017 USD ($) Bcf	Jun. 30, 2016 USD ($) Bcf	Jun. 30, 2017 USD ($) Bcf	Jun. 30, 2016 USD ($) Bcf	Sep. 30, 2016 USD ($) Bcf
Related Party Transaction
Related party costs incurred	$ 2,961	$ 2,811	$ 10,059	$ 8,789
UGI and Subsidiaries \| Administrative Services
Related Party Transaction
Amount of related party transaction	$ 562	$ 1,752	$ 3,420	$ 3,904
Energy Services
Related Party Transaction
Volume of gas storage inventory (in bcf of natural gas) \| Bcf	3.6	2.7	3.6	2.7	4.6
Natural gas storage inventory, related parties, current	$ 10,662	$ 5,100	$ 10,662	$ 5,100	$ 11,148
Revenue from related parties	10,554	4,514	$ 43,836	26,134
Term of agreements (in years)			1 year
Purchases from related party	14,675	6,928	$ 75,783	30,032
Energy Services \| SCAAs
Related Party Transaction
Amount of related party transaction	729	493	$ 2,027	1,510
SCAA contract term (in years)			3 years
Related party costs incurred	9,777	4,358	$ 12,272	6,387
Related party security deposits	11,040	8,100	11,040	8,100	$ 8,100
Energy Services \| Exclusive of Transactions Pursuant SCAAs
Related Party Transaction
Related party costs incurred	$ 2,137	$ 2,138	$ 73,872	$ 61,193

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