Goodwill and Intangible Assets (Details 1) (USD $) In Millions	12 Months Ended		12 Months Ended		12 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 AmeriGas Propane [Member]	Sep. 30, 2010 AmeriGas Propane [Member]	Sep. 30, 2011 Gas Utility [Member]	Sep. 30, 2009 Gas Utility [Member]	Sep. 30, 2010 Midstream & Marketing [Member]	Sep. 30, 2011 Midstream & Marketing [Member]	Sep. 30, 2011 International Propane, Antargaz [Member]	Sep. 30, 2010 International Propane, Antargaz [Member]	Sep. 30, 2011 International Propane, Other [Member]	Sep. 30, 2010 International Propane, Other [Member]	Sep. 30, 2010 Corporate & Other & Elims [Member]	Sep. 30, 2011 Corporate & Other & Elims [Member]
Changes in the carrying amount of goodwill
Goodwill, Beginning Balance	$ 1,562.7	$ 1,582.3	$ 683.1	$ 670.1	$ 180.1	$ 180.1	$ 11.8	$ 2.8	$ 602.7	$ 646.9	$ 87.0	$ 70.4	$ 3.0	$ 7.0
Goodwill acquired	13.1	33.5	13.1	12.9								20.6
Purchase accounting adjustments	(1.0)	0.1	0.1	0.1	2.0						(3.2)
Dispositions		(5.0)					(9.0)						4.0
Foreign currency translation	(12.6)	(48.2)							(10.9)	(44.2)	(1.6)	(4.0)
Goodwill, Ending Balance	$ 1,562.2	$ 1,562.7	$ 696.3	$ 683.1	$ 182.1	$ 180.1	$ 2.8	$ 2.8	$ 591.8	$ 602.7	$ 82.2	$ 87.0	$ 7.0	$ 7.0

Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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