Pension And Other Postretirement Benefit Plans (Components Of Net Periodic Pension Expense) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Interest cost	$ 0.4	$ 0.5
Net periodic pension cost	0.6	0.7	0.8
Defined Benefit Pension Plans [Member]
Service cost, net of employee contributions	26.1	24.6	19.9
Interest cost	19.0	18.9	17.4
Expected return on plan assets	(23.2)	(22.0)	(20.4)
Amortization of net loss	8.4	6.9	3.1
Amortization of prior service cost	(0.2)		0.1
Net periodic pension cost	$ 30.1	$ 28.4	$ 20.1