Equity (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Changes in Accumulated Other Comprehensive Income (Loss)
January 1	$ (1,356.0)	$ (1,015.4)
Other comprehensive income (loss) before reclassifications	388.8	(81.8)
Reclassification from accumulated other comprehensive income (loss)	9.0	7.5
September 30	(958.2)	(1,089.7)
Cash Flow Hedge
Changes in Accumulated Other Comprehensive Income (Loss)
January 1	(29.5)	(3.3)
Other comprehensive income (loss) before reclassifications	0.0	(28.5)
Reclassification from accumulated other comprehensive income (loss)	2.4	1.5
September 30	(27.1)	(30.3)
Available-for-Sale Securities
Changes in Accumulated Other Comprehensive Income (Loss)
January 1	(0.8)	(0.9)
Other comprehensive income (loss) before reclassifications	0.3	0.1
Reclassification from accumulated other comprehensive income (loss)	0.0	0.0
September 30	(0.5)	(0.8)
Defined Benefit Pension Plans and Postemployment Arrangements
Changes in Accumulated Other Comprehensive Income (Loss)
January 1	(90.6)	(87.9)
Other comprehensive income (loss) before reclassifications	0.0	0.0
Reclassification from accumulated other comprehensive income (loss)	6.6	6.0
September 30	(84.0)	(81.9)
Foreign Currency Translation
Changes in Accumulated Other Comprehensive Income (Loss)
January 1	(1,235.1)	(923.3)
Other comprehensive income (loss) before reclassifications	388.5	(53.4)
Reclassification from accumulated other comprehensive income (loss)	0.0	0.0
September 30	$ (846.6)	$ (976.7)

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e681-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=84158357&loc=d3e1436-108581

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 220
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-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=84158357&loc=d3e1436-108581

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