Pension And Other Post-Retirement Benefits (Net Periodic Benefit Expense Related To Post-Retirement Plans) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 4.5	$ 3.7
Interest cost	3.2	3.2
Expected return on plan assets	(3.1)	(3.0)
Amortization of net actuarial loss from earlier periods	2.5	1.1
Amortization of net prior service costs from earlier periods	0.2	0.2
Total to be recognized as components of net periodic expense	7.3	5.2
Other Post-Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.3	0.3
Interest cost	0.2	0.2
Amortization of net actuarial loss from earlier periods	0.1
Total to be recognized as components of net periodic expense	$ 0.6	$ 0.5