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Financial Instruments (Details Textual 2) $ in Millions, ₩ in Billions | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2018 USD ($) | Dec. 31, 2018 KRW (₩) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2019 KRW (₩) | Dec. 31, 2018 KRW (₩) | Feb. 29, 2012 USD ($) | Feb. 29, 2012 KRW (₩)
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Sale of Ionis common stock |  |  | $ 479.3 | $ 0.0 | $ 0.0 |  |  |  |
Payments to increase investment in Samsung Bioepis |  |  | 0.0 | 676.6 | $ 0.0 |  |  |  |
Strategic Investments |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Strategic investment portfolio | $ 676.3 |  | 393.9 | $ 676.3 |  |  |  |  |
Ionis Pharmaceuticals |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Sale of Ionis common stock |  |  | $ 382.0 |  |  |  |  |  |
Samsung Bioepis |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Samsung Bioepis, ownership percentage before additional purchase transaction | 5.00% |  |  | 5.00% |  |  | 5.00% |  |
Samsung Bioepis, ownership percentage |  |  | 49.90% |  |  | 49.90% |  | 15.00% | 15.00%
Payments to increase investment in Samsung Bioepis | $ 676.6 | ₩ 759.5 |  |  |  |  |  |  |
Investment in Samsung Bioepis | $ 680.6 |  | $ 580.2 | $ 680.6 |  | ₩ 670.8 | ₩ 759.5 | $ 45.0 | ₩ 49.5

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