Accumulated Other Comprehensive Income/(Loss) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Changes in accumulated other comprehensive income (loss) by component
Balance at the beginning of the period			$ 1,750.9
Balance at the end of the period	$ 1,984.3		1,984.3
Foreign Currency Translation
Changes in accumulated other comprehensive income (loss) by component
Balance at the beginning of the period	(205.7)	$ (114.6)	(230.0)	$ (113.5)
Other comprehensive income (loss) before reclassifications	36.0	(55.5)	60.3	(56.6)
Net current period other comprehensive income (loss)	36.0	(55.5)	60.3	(56.6)
Balance at the end of the period	(169.7)	(170.1)	(169.7)	(170.1)
Other
Changes in accumulated other comprehensive income (loss) by component
Balance at the beginning of the period	(19.3)	(8.1)	(20.7)	(9.0)
Other comprehensive income (loss) before reclassifications	2.8	0.6	4.2	1.5
Net current period other comprehensive income (loss)	2.8	0.6	4.2	1.5
Balance at the end of the period	(16.5)	(7.5)	(16.5)	(7.5)
Accumulated Other Comprehensive Income (Loss)
Changes in accumulated other comprehensive income (loss) by component
Balance at the beginning of the period	(225.0)	(122.7)	(250.7)	(122.5)
Other comprehensive income (loss) before reclassifications	38.8	(54.9)	64.5	(55.1)
Net current period other comprehensive income (loss)	38.8	(54.9)	64.5	(55.1)
Balance at the end of the period	$ (186.2)	$ (177.6)	$ (186.2)	$ (177.6)

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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