Debt (Energy Services) (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2012
Debt Instrument [Line Items]
Amount of net assets restricted from transfer to UGI under different agreements		$ 1,400
Energy services credit agreement [Member]
Debt Instrument [Line Items]
Credit agreement	170
Ratio of consolidated total indebtedness to EBITDA	2.00
Letters of Credit Outstanding, Amount	10.0	85.0
Rate of Interest above LIBOR Rate	3.00%
Rate of Interest above Alternate Base Rate	2.00%
Rate of interest above Federal fund Rate	0.50%
Rate of interest above one month LIBOR Rate	1.00%
Line of Credit Facility, Interest Rate at Period End	3.25%	3.25%
Minimum consolidated total indebtedness for maximum ratio of Consolidated total indebtedness to Consolidated total capitalization	250
Minimum Consolidated Net Worth, for Maximum Ratio of Consolidated Total Indebtedness to Consolidated Total Capitalization	150
Receivables securitization facility under energy services	200
Letter of Credit [Member] | Energy services credit agreement [Member]
Debt Instrument [Line Items]
Revolving Credit Agreement Sublimit for Letters of Credit	$ 50