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Other Expense Items (Details) $ in Millions	3 Months Ended		6 Months Ended
Other Expense Items (Details) $ in Millions	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Feb. 17, 2016	Dec. 31, 2015	Jun. 30, 2013 USD ($)
Summary of Investment Holdings [Line Items]
Venezuela currency devaluation	$ 0.0	$ 0.0	$ 0.0	$ 2.7
Venezuela deconsolidation	(11.1)	0.0	(11.1)	0.0
Development income	(0.4)	$ (0.4)	(0.8)	$ (0.8)
Nonrefundable payment from customer	13.6		13.6				$ 20.0
Unearned income, current	1.5		1.5
Unearned income, noncurrent	$ 12.1		$ 12.1
VENEZUELA
Summary of Investment Holdings [Line Items]
Foreign Currency Exchange Rate, Remeasurement					10.0	6.3