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Collaborative and Other Relationships Collaborative and Other Relationships - Equity Method Investments (Details) $ in Millions, ₩ in Billions | 1 Months Ended | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | ---
Feb. 29, 2012 USD ($) | Jun. 30, 2016 USD ($) | Jun. 30, 2015 USD ($) | Dec. 31, 2013 USD ($) | Jun. 30, 2016 USD ($) | Jun. 30, 2015 USD ($) | Feb. 29, 2012 KRW (₩)
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Recognized loss |  | $ 0.0 | $ (4.9) |  | $ 0.0 | $ (5.7) |
Research and development |  | 473.1 | 490.7 |  | 910.4 | 951.3 |
Revenue related to technical development and technology transfer services |  | $ 79.0 | 55.6 |  | $ 166.9 | 107.6 |
Samsung Biosimilar Agreement [Member] |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Contribution from Samsung to develop, manufacture and market biosimilar pharmaceuticals | $ 250.0 |  |  |  |  |  | ₩ 280.5
Variable interest entity, qualitative or quantitative information, ownership percentage | 85.00% |  |  |  |  |  |
Contribution from Biogen to develop, manufacture and market biosimilar pharmaceuticals | $ 45.0 |  |  |  |  |  | ₩ 49.5
Percentage of stake in entity minimum | 15.00% | 9.00% |  |  | 9.00% |  | 15.00%
Percentage of stake in entity maximum | 49.90% |  |  |  |  |  |
Recognized loss |  |  | (4.9) |  |  | (5.7) |
Research and development |  |  |  | $ 46.0 |  |  |
Expected profit share with Samsung Bioepis |  |  |  | 50.00% |  |  |
Revenue related to technical development and technology transfer services |  | $ 14.2 | $ 17.2 |  | $ 16.9 | $ 36.1 |
Acquired and in-licensed rights and patents | Biosimilars |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Increase in acquired and in-licensed rights and patents |  | $ 25.0 |  |  | $ 50.0 |  |

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