Employee Benefits (Net Periodic Cost) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Net periodic benefit cost:
Service cost	$ 3.9	$ 3.6	$ 3.6
Interest cost	59.3	61.2	60.1
Expected return on plan assets	(51.1)	(43.0)	(52.4)
Amortization of prior net loss	9.0	9.6	6.2
Curtailment and settlement loss, net	0	0	1.3
Net periodic pension cost	21.1	31.4	18.8
Other changes in plan assets and benefit obligations recognized in other comprehensive loss:
Net actuarial loss (gain) and other adjustments	170.4	3.6	105.3
Less amortization of prior losses	(9.0)	(9.6)	(6.2)
Total recognized in other comprehensive loss (income)	161.4	(6.0)	99.1
Total recognized in net periodic benefit cost and other comprehensive loss	182.5	25.4	117.9
Income tax provision (benefit) related to amounts in other comprehensive income	$ (1.3)	$ 0	$ 2.5