Other Comprehensive Loss - OCI (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Foreign currency translation adjustments [Abstract]
Foreign currency translation	$ 4.9	$ 27.2	$ 25.0	$ 37.1
Foreign currency translation, tax	0.0	0.0	0.0	0.0
Foreign currency translation, net of tax	4.9	27.2	25.0	37.1
Changes in fair value of cash flow hedges:
Changes in fair value of cash flow hedges, before tax	0.5	(0.1)	4.2	(0.5)
Changes in fair value of cash flow hedges, tax	(0.1)	0.0	(0.5)	0.1
Changes in fair value of cash flow hedges, net of tax	0.4	(0.1)	3.7	(0.4)
Total other comprehensive earnings [Abstract]
Other comprehensive loss, before tax	5.4	27.1	29.2	36.6
Other comprehensive loss, tax	(0.1)	0.0	(0.5)	0.1
Other comprehensive earnings, net of tax	5.3	27.1	28.7	36.7
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	$ (0.4)	$ (0.1)	$ 1.3	$ 0.1

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