Summary of Significant Accounting Policies - Schedule of Changes in Accumulated Other Comprehensive Income (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Accumulated Other Comprehensive Income (Loss), Net Of Tax
Accumulated Other Comprehensive Income (Loss) - Balance at beginning of year	$ 8.4
Other comprehensive (loss) income before reclassification adjustments (after-tax)	5.8
Amounts reclassified from AOCI and noncontrolling interests:
Reclassification adjustments (pre-tax)	(45.6)
Reclassification adjustments tax (expense) benefit	1.4
Reclassification adjustments (after-tax)	(44.2)
Other comprehensive (loss) income	(38.4)	106.4	(82.2)
Add comprehensive loss attributable to noncontrolling interests, principally in AmeriGas Partners	8.8
Comprehensive income attributable to UGI Corporation	(29.6)
Accumulated Other Comprehensive Income (Loss) - Balance at end of year	(21.2)	8.4
Postretirement Benefit Plans
Accumulated Other Comprehensive Income (Loss), Net Of Tax
Accumulated Other Comprehensive Income (Loss) - Balance at beginning of year	(16.4)
Other comprehensive (loss) income before reclassification adjustments (after-tax)	(5.2)
Amounts reclassified from AOCI and noncontrolling interests:
Reclassification adjustments (pre-tax)	1.6
Reclassification adjustments tax (expense) benefit	(0.6)
Reclassification adjustments (after-tax)	1.0
Other comprehensive (loss) income	(4.2)
Add comprehensive loss attributable to noncontrolling interests, principally in AmeriGas Partners	0
Comprehensive income attributable to UGI Corporation	(4.2)
Accumulated Other Comprehensive Income (Loss) - Balance at end of year	(20.6)
Derivative Instruments
Accumulated Other Comprehensive Income (Loss), Net Of Tax
Accumulated Other Comprehensive Income (Loss) - Balance at beginning of year	(26.9)
Other comprehensive (loss) income before reclassification adjustments (after-tax)	54.0
Amounts reclassified from AOCI and noncontrolling interests:
Reclassification adjustments (pre-tax)	(47.2)
Reclassification adjustments tax (expense) benefit	2.0
Reclassification adjustments (after-tax)	(45.2)
Other comprehensive (loss) income	8.8
Add comprehensive loss attributable to noncontrolling interests, principally in AmeriGas Partners	8.8
Comprehensive income attributable to UGI Corporation	17.6
Accumulated Other Comprehensive Income (Loss) - Balance at end of year	(9.3)
Foreign Currency
Accumulated Other Comprehensive Income (Loss), Net Of Tax
Accumulated Other Comprehensive Income (Loss) - Balance at beginning of year	51.7
Other comprehensive (loss) income before reclassification adjustments (after-tax)	(43.0)
Amounts reclassified from AOCI and noncontrolling interests:
Reclassification adjustments (pre-tax)	0
Reclassification adjustments tax (expense) benefit	0
Reclassification adjustments (after-tax)	0
Other comprehensive (loss) income	(43.0)
Add comprehensive loss attributable to noncontrolling interests, principally in AmeriGas Partners	0
Comprehensive income attributable to UGI Corporation	(43.0)
Accumulated Other Comprehensive Income (Loss) - Balance at end of year	$ 8.7