Accumulated Other Comprehensive Income/(Loss) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 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	$ 2,079.0		2,079.0
Foreign Currency Translation
Changes in accumulated other comprehensive income (loss) by component
Balance at the beginning of the period	(169.7)	$ (170.1)	(230.0)	$ (113.5)
Other comprehensive income (loss) before reclassifications	31.0	(9.9)	91.3	(66.5)
Net current period other comprehensive income (loss)	31.0	(9.9)	91.3	(66.5)
Balance at the end of the period	(138.7)	(180.0)	(138.7)	(180.0)
Other
Changes in accumulated other comprehensive income (loss) by component
Balance at the beginning of the period	(16.5)	(7.5)	(20.7)	(9.0)
Other comprehensive income (loss) before reclassifications	3.6	(1.2)	7.8	0.3
Net current period other comprehensive income (loss)	3.6	(1.2)	7.8	0.3
Balance at the end of the period	(12.9)	(8.7)	(12.9)	(8.7)
Accumulated Other Comprehensive Income (Loss)
Changes in accumulated other comprehensive income (loss) by component
Balance at the beginning of the period	(186.2)	(177.6)	(250.7)	(122.5)
Other comprehensive income (loss) before reclassifications	34.6	(11.1)	99.1	(66.2)
Net current period other comprehensive income (loss)	34.6	(11.1)	99.1	(66.2)
Balance at the end of the period	$ (151.6)	$ (188.7)	$ (151.6)	$ (188.7)

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
-Section 55
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Amount after tax of other comprehensive income (loss) attributable to parent entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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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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