Interest Income, Expense and Other Finance Costs (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2016
Interest Income, Expense, And Other Financing Costs [Abstract]
Interest income		$ 1.0	$ 1.3
Interest expense and other financing costs		(13.7)	(8.9)
Interest expense and other financing costs, net	[1]	$ (12.7)	$ (7.6)

[1] Amounts may not add due to rounding