Special Charges (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Special charges for workforce reductions and advisory costs	$ 0.0	$ (2.9)	$ (0.1)	$ (3.0)
Termination benefit costs			(0.1)
Restructuring cost, settled without cash			0.1
Contract Termination [Member]
Termination benefit costs			$ 0.0	$ 2.9

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Publisher FASB
-Name Accounting Standards Codification
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