Cost Reduction Plans - Summary of the CIP Reserve Activity (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018 USD ($)
Restructuring Cost and Reserve [Line Items]
Beginning balance	$ 33.4
Accrual	1.2
Payments	(4.9)
Ending balance	29.7
Severance
Restructuring Cost and Reserve [Line Items]
Beginning balance	30.0
Accrual	0.0
Payments	(2.9)
Ending balance	27.1
Retention
Restructuring Cost and Reserve [Line Items]
Beginning balance	3.4
Accrual	1.2
Payments	(2.0)
Ending balance	$ 2.6