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Equity Method Investments in Affiliates - Change in Equity Method Investments (Details) - USD ($) $ in Millions | 6 Months Ended
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Jun. 30, 2018 | Jun. 30, 2017
Change in Equity Method Investments in Affiliates [Roll Forward] |  |
Balance, as of December 31, 2017 | $ 3,304.7 |
Distributions of earnings from equity method investments | (327.8) | $ (283.5)
Balance, as of June 30, 2018 | 3,134.0 |
Equity Method Investee |  |
Change in Equity Method Investments in Affiliates [Roll Forward] |  |
Balance, as of December 31, 2017 | 3,304.7 |
Equity method earnings | 218.4 |
Equity method intangible amortization and impairments | (86.8) |
Distributions of earnings from equity method investments | (327.8) |
Foreign currency translation | 31.3 |
Other | (5.8) |
Balance, as of June 30, 2018 | $ 3,134.0 |

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- Definition Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(10)) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(12)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 21D -URI http://asc.fasb.org/extlink&oid=98514028&loc=SL94080555-108585 + Details
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- Definition Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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