Restructuring Charges (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)
Restructuring and Related Cost, Number of Positions Eliminated			627
Severance and termination costs	$ 2.1		$ 22.0
Lease impairment cost	0.0		11.9
Restructuring charges	2.1	$ 0.0	33.9
Payments for Restructuring			(14.5)
Restructuring Reserve	$ 7.5		7.5	$ 0.0
IAN [Member]
Restructuring charges			27.6
CMG [Member]
Restructuring charges			$ 5.6

Amount of loss from impairment of right-of-use asset from operating lease.

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