Special Charges (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Special charges for workforce reductions and advisory costs	$ (0.1)	$ 0.6
Termination benefit costs	0.0	0.7
Other restructuring costs		0.1
Restructuring cost, settled without cash		$ 0.2
Contract Termination [Member]
Termination benefit costs	0.0
Restructuring liability, current	$ 3.2

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

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