Pension And Other Postretirement Benefits (Components Of Net Periodic Benefit Cost) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2012	Mar. 31, 2011
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0.6	$ 0.4	$ 1.3	$ 0.9
Interest cost	3.0	2.7	5.9	5.5
Expected return on plan assets	(4.6)	(4.2)	(9.3)	(8.5)
Amortization of net loss	1.6	1.1	3.2	2.2
Net periodic benefit cost	0.6		1.1	0.1
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.1	(0.1)	0.1	(0.1)
Interest cost	0.4	0.4	0.9	0.8
Amortization of net loss	0.1	0.1	0.2
Net periodic benefit cost	$ 0.6	$ 0.4	$ 1.2	$ 0.7