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Restructuring and Other Expense - Schedule of Restructuring Reserve Activity (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Restructuring Reserve [Roll Forward]
Charges	$ 0.0		$ (0.7)	$ 0.1	$ (0.7)
Restructuring Plan \| Severance and Related
Restructuring Reserve [Roll Forward]
Accrued balance, beginning balance	0.0	$ 0.0		0.0
Charges		0.1
Usage and payments		(0.1)
Accrued balance, ending balance	$ 0.0	$ 0.0		$ 0.0