Cost Reduction Plans - Summary of the CIP Reserve Activity (Details) $ in Millions	6 Months Ended
Jun. 30, 2018 USD ($)
Restructuring Cost and Reserve [Line Items]
Beginning balance	$ 33.4
Accrual	2.7
Payments	(7.8)
Ending balance	28.3
Severance
Restructuring Cost and Reserve [Line Items]
Beginning balance	30.0
Accrual	0.0
Payments	(5.4)
Ending balance	24.6
Retention
Restructuring Cost and Reserve [Line Items]
Beginning balance	3.4
Accrual	2.7
Payments	(2.4)
Ending balance	$ 3.7

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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