Income Taxes (Details 1) (USD $) In Millions	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Current expenses:
Federal	$ 24.4	$ 60.5	$ 69.6
State	14.5	20.4	21.6
Foreign	15.0	25.8	41.1
Investment tax credit	(5.8)	(1.7)
Total current expense	48.1	105.0	132.3
Deferred expense (benefit):
Federal	79.3	54.5	27.6
State	2.4	6.4	(1.1)
Foreign	1.4	2.1	0.7
Investment tax credit amortization	(0.4)	(0.4)	(0.4)
Total deferred expense	82.7	62.6	26.8
Total income tax expense	$ 130.8	$ 167.6	$ 159.1