Income Taxes - Income Tax (Benefit) Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
U.S.:
Federal	$ 0.1	$ 0.7	$ (0.6)
State and local	0.4	(0.2)	0.4
Foreign	85.5	120.1	36.7
Total current	86.0	120.6	36.5
U.S.:
Federal	1.9	6.4	(18.3)
State and local	(0.2)	(5.2)	0.4
Foreign	(59.1)	(46.7)	(25.3)
Total deferred	(57.4)	(45.5)	(43.2)
Income tax expense (benefit)	$ 28.6	$ 75.1	$ (6.7)