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Financial Instruments Financial Instruments (Details Textual 2) - USD ($) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018
Business Acquisition [Line Items] |  |  |
Proceeds from sales of strategic investments | $ 309.7 | $ 0.0 |
Strategic Investments |  |  |
Business Acquisition [Line Items] |  |  |
Strategic investment portfolio | 569.8 |  |
Ionis Pharmaceuticals |  |  |
Business Acquisition [Line Items] |  |  |
Proceeds from sales of strategic investments | 213.3 |  |
Other current assets | Strategic Investments |  |  |
Business Acquisition [Line Items] |  |  |
Strategic investment portfolio | $ 164.2 |  |
Other noncurrent assets | Strategic Investments |  |  |
Business Acquisition [Line Items] |  |  |
Strategic investment portfolio |  |  | $ 676.3

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- Definition The cash inflow associated with the sale of equity securities classified as available-for-sale securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26853-111562 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585 + Details
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