Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2015	Jun. 30, 2015
Accounting Policies [Abstract]
Decrease in other comprehensive (loss) income	$ 57.8	$ 10.7

Quantifying Immaterial Error, Not Corrected, Amount

No definition available.

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Namespace Prefix:	ugi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration