Other Income Net (Details) (USD $) In Millions	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Other Income Net
Interest and interest related income	$ 2.3	$ 2.9	$ 5.0
Antargaz competition authority matter	9.4		(10.0)
Utility non-Tariff service income	6.4	2.4	3.2
Foreign currency hedge loss	(6.1)
Gain on sale of Partnership LPG storage facility			39.9
Gain on sale of Atlantic Energy, LLC		36.5
Finance charges	15.1	11.3	11.7
Partnership interest rate protection agreement losses		(12.2)	(1.7)
Other, Net	19.4	17.1	7.8
Other income, net	$ 46.5	$ 58.0	$ 55.9