Pension Plans and Other Postretirement Benefits (Details 8) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Prior service (cost) credit	$ (3.6)	$ (4.9)
Net actuarial loss	(1,414.6)	(1,347.2)
Accumulated other comprehensive loss	(1,418.2)	(1,352.1)	$ (1,016.4)
Deferred tax effect	529.9	514.7
Accumulated other comprehensive loss, net of tax	(888.3)	(837.4)
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Prior service (cost) credit	(6.9)	(11.8)
Net actuarial loss	(94.5)	(141.1)
Accumulated other comprehensive loss	(101.4)	(152.9)	$ (151.5)
Deferred tax effect	38.5	58.8
Accumulated other comprehensive loss, net of tax	$ (62.9)	$ (94.1)