Other Comprehensive Loss - OCI (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Foreign currency translation adjustments [Abstract]
Foreign currency translation	$ 5.4	$ (4.0)	$ 20.1	$ 9.9
Foreign currency translation, tax	0.0	0.0	0.0	0.0
Foreign currency translation, net of tax	5.4	(4.0)	20.1	9.9
Changes in fair value of cash flow hedges:
Changes in fair value of cash flow hedges, before tax	1.5	(2.0)	3.7	(0.4)
Changes in fair value of cash flow hedges, tax	(0.2)	0.1	(0.4)	0.1
Changes in fair value of cash flow hedges, net of tax	1.3	(1.9)	3.3	(0.3)
Total other comprehensive earnings [Abstract]
Other comprehensive loss, before tax	6.9	(6.0)	23.8	9.5
Other comprehensive loss, tax	(0.2)	0.1	(0.4)	0.1
Other comprehensive earnings, net of tax	6.7	(5.9)	23.4	9.6
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	$ 0.3	$ 0.3	$ 1.7	$ 0.2

Amount before tax, after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss), attributable to parent entity.

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