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Fair Value Measurements (Details Textual) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 | Dec. 31, 2017
Business Acquisition, Contingent Consideration [Line Items] |  |
Asset impairment charges | $ 0.0 |
Changes in valuation techniques | 0 |
Contingent consideration obligations | $ 273.7 | $ 279.0
2.900% Senior Notes due 2020 |  |
Business Acquisition, Contingent Consideration [Line Items] |  |
Senior Notes interest rate | 2.90% |
3.625% Senior Notes due 2022 |  |
Business Acquisition, Contingent Consideration [Line Items] |  |
Senior Notes interest rate | 3.625% |
4.050% Senior Notes due 2025 |  |
Business Acquisition, Contingent Consideration [Line Items] |  |
Senior Notes interest rate | 4.05% |
5.200% Senior Notes due 2045 |  |
Business Acquisition, Contingent Consideration [Line Items] |  |
Senior Notes interest rate | 5.20% |

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- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228 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 + Details
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- Definition Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 25 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 35 -Paragraph 1 -Subparagraph b -URI http://asc.fasb.org/extlink&oid=6911338&loc=d3e6819-128478 + Details
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