Pension and Other Postretirement Benefits - Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Selling, General and Administrative Expense	$ 293.0	$ 276.4	$ 851.0	$ 810.5
Non-operating Expense	5.9	7.8	18.8	22.8
Pension Plans, Defined Benefit
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Service cost	6.4	7.1	19.2	21.4
Selling, General and Administrative Expense	6.4	7.1	19.2	21.4
Interest cost	7.5	6.8	22.5	20.5
Expected return on plan assets	(8.5)	(7.9)	(25.5)	(23.9)
Amortization of: Net actuarial loss	4.8	6.7	14.3	19.9
Amortization of: Prior service cost (gain)	0.0	0.0	0.0	0.2
Non-operating Expense	3.8	5.6	11.3	16.7
Net periodic benefit cost	10.2	12.7	30.5	38.1
Other Postretirement Benefit Plans, Defined Benefit
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Service cost	0.5	0.5	1.5	1.7
Selling, General and Administrative Expense	0.5	0.5	1.5	1.7
Interest cost	0.7	0.6	2.2	2.0
Expected return on plan assets	0.0	0.0	0.0	0.0
Amortization of: Net actuarial loss	0.0	0.3	0.2	0.7
Amortization of: Prior service cost (gain)	0.0	(0.5)	0.0	(1.5)
Non-operating Expense	0.7	0.4	2.4	1.2
Net periodic benefit cost	$ 1.2	$ 0.9	$ 3.9	$ 2.9