Inventories (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2016 USD ($) agreement Bcf	Sep. 30, 2015 USD ($) Bcf
Public Utilities, Inventory
Volume of gas storage inventories released under SCAAs with non-affiliates (in bcf) | Bcf	8.1	9.0
Carrying value of gas storage inventories released under SCAAs with non-affiliates | $	$ 18,773	$ 22,694
SCAAs
Public Utilities, Inventory
Number of storage agreements	3
SCAAs | Other Current Liabilities
Public Utilities, Inventory
Security deposit liability | $	$ 19,100	$ 17,700
SCAAs | UGI Energy Services, Inc
Public Utilities, Inventory
Number of Storage Agreements with Energy Services	1
SCAAs | Third Party
Public Utilities, Inventory
Number of Storage Agreements with Non-Affiliates	2
SCAAs | Maximum | UGI Energy Services, Inc
Public Utilities, Inventory
Storage agreement, term (in years)	3 years