Employee Benefits (Net Periodic Cost) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net periodic benefit cost:
Service cost	$ 4.6	$ 4.3	$ 4.3
Interest cost	57.2	60.7	56.2
Expected return on plan assets	(59.9)	(53.7)	(55.6)
Amortization of prior net loss	16.0	12.8	14.8
Settlement loss	28.7	0.0	0.0
Net periodic pension cost	46.6	24.1	19.7
Other changes in plan assets and benefit obligations recognized in other comprehensive loss (income):
Net actuarial loss (gain) and other adjustments	(52.0)	126.3	(107.7)
Less amortization of prior losses	(16.0)	(12.8)	(14.8)
Settlement adjustment	(28.7)	0.0	0.0
Total recognized in other comprehensive loss (income)	(96.7)	113.5	(122.5)
Total recognized in net periodic benefit cost and other comprehensive (income) loss	(50.1)	137.6	(102.8)
Income tax provision (benefit) related to amounts in other comprehensive income	$ 12.2	$ 0.2	$ 42.7