Employee Retirement Plans (Details)			12 Months Ended
	Sep. 30, 2011 USD ($)	Sep. 30, 2010 USD ($)	Sep. 30, 2011 Pension Benefit [Member] USD ($)	Sep. 30, 2010 Pension Benefit [Member] USD ($)	Sep. 30, 2009 Pension Benefit [Member] USD ($)	Sep. 30, 2011 Other Postretirement Benefits [Member] USD ($)	Sep. 30, 2010 Other Postretirement Benefits [Member] USD ($)	Sep. 30, 2009 Other Postretirement Benefits [Member] USD ($)	Sep. 30, 2009 Other Postretirement Benefits [Member] EUR (€)
Change in benefit obligations:
Benefit obligations - beginning of year			$ 471,800,000	$ 428,900,000		$ 22,900,000	$ 21,400,000
Service cost			8,800,000	8,700,000	7,100,000	400,000	400,000	300,000
Interest cost			24,100,000	23,500,000	23,300,000	1,100,000	1,100,000	1,200,000
Actuarial loss			(22,000,000)	32,200,000		(2,400,000)	1,600,000
Plan amendments						(100,000)
Plan settlements				(2,700,000)
Foreign currency			(100,000)	(500,000)			(200,000)
Benefits paid			(19,700,000)	(18,300,000)		(1,400,000)	(1,400,000)
Benefit obligations - end of year			462,900,000	471,800,000	428,900,000	20,500,000	22,900,000	21,400,000
Change in plan assets:
Fair value of plan assets - beginning of year			287,900,000	279,800,000		10,000,000	9,700,000
Actual gain on plan assets			2,600,000	25,900,000		100,000	700,000
Foreign currency				(200,000)
Employer Contribution			19,200,000	3,400,000	0	1,100,000	1,000,000
Settlement of obligation under retirement benefit plan				(2,700,000)		18,700,000		5,700,000	4,100,000
Benefits paid			(19,700,000)	(18,300,000)		(1,400,000)	(1,400,000)
Fair value of plan assets - end of year			290,000,000	287,900,000	279,800,000	9,800,000	10,000,000	9,700,000
Funded status of the plans - end of year			(172,900,000)	(183,900,000)		(10,700,000)	(12,900,000)
(Liabilities) recorded in the balance sheet:
Unfunded liabilities - included in other current liabilities			(27,600,000)	(20,300,000)
Unfunded liabilities - included in other noncurrent liabilities			(145,300,000)	(163,600,000)		(10,700,000)	(12,900,000)
Net amount recognized			(172,900,000)	(183,900,000)		(10,700,000)	(12,900,000)
Amounts recorded in UGI Corporation stockholders' equity (pre-tax):
Prior service (credit) cost			(200,000)	(400,000)		(100,000)	100,000
Net actuarial loss (gain)	(7,600,000)	(4,700,000)	13,600,000	13,800,000		(800,000)	100,000
Total			13,400,000	13,400,000		(900,000)	200,000
Amounts recorded in regulatory assets and liabilities (pre-tax):
Prior service cost (credit)			1,800,000	300,000		(3,200,000)	(3,400,000)
Net actuarial loss			146,900,000	155,600,000		6,300,000	5,900,000
Total			$ 148,700,000	$ 155,900,000		$ 3,100,000	$ 2,500,000