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Collaborative and Other Relationships (Details Textual) $ in Millions, ₩ in Billions | 1 Months Ended | 3 Months Ended | 6 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Feb. 29, 2012 USD ($) | Dec. 31, 2016 USD ($) | Sep. 30, 2016 USD ($) | Jun. 30, 2016 USD ($) | Mar. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Sep. 30, 2015 USD ($) | Jun. 30, 2015 USD ($) | Mar. 31, 2015 USD ($) | Jun. 30, 2014 USD ($) | Dec. 31, 2013 USD ($) | Sep. 30, 2013 USD ($) | Dec. 31, 2012 USD ($) | Jun. 30, 2012 USD ($) | Mar. 31, 2012 USD ($) | Jun. 30, 2016 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($) | Mar. 31, 2014 USD ($) | Feb. 29, 2012 KRW (₩) | Jan. 31, 2007
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue on sales in the rest of world for RITUXAN |  |  | $ 2,502.9 | $ 2,539.6 | $ 2,466.0 | $ 2,309.4 | $ 2,425.9 | $ 2,391.7 | $ 2,198.6 | $ 2,172.3 |  |  |  |  |  |  |  | $ 9,817.9 | $ 9,188.5 | $ 8,203.4 |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,973.3 | 2,012.8 | 1,893.4 |  |  |
Other revenues from external customers |  |  | 50.9 | $ 98.6 | 79.0 | $ 87.9 | 79.5 | 49.0 | $ 55.6 | $ 52.0 |  |  |  |  |  |  |  | 316.4 | 236.1 | 304.5 |  |  |
Prepaid research and development |  |  | 1,335.8 |  |  |  | 1,107.6 |  |  |  |  |  |  |  |  |  |  | 1,335.8 | 1,107.6 |  |  |  |
Potential future milestone payments commitment, approximately |  |  | 3,100.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3,100.0 |  |  |  |  |
Income (Loss) from Equity Method Investments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.0 | (12.5) | (15.1) |  |  |
Biogen Hemophilia |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock acquired in acquisition |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100.00%
Acorda |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Expected additional milestone payments for successful achievement of regulatory and commercial sales milestones |  |  | 375.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 375.0 |  |  |  |  |
Expected additional milestone payments when certain sales threshold is met |  |  | 15.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 15.0 |  |  |  |  |
Foreign sales required to trigger milestone |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100.0 |  |  |  |  |
Biogen's share of expense reflected within our consolidation statements of income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 31.5 | 30.6 | 29.2 |  |  |
AbbVie |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Biogen's share of pre-tax profits in the U.S. for RITUXAN and GAZYVA, including the reimbursement of selling and development expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 21.9 |  |  |  |  |
Total expense incurred by collaboration |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 50.0 |  |  |  |  |
Biogen share of co-promotion profits or losses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 50.00% |  |  |  |  |
Swedish Orphan Biovitrum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consideration per product |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 10.0 |  |  |  |  |
Reimbursement cost achieving period |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6 years |  |  |  |  |
Time period for paying remaining balance due |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 90 days |  |  |  |  |
Ionis Pharmaceuticals, Inc. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  | $ 75.0 | $ 30.0 |  |  |  | $ 5.5 | 20.0 | 20.0 |  |  |
Term of collaboration agreement |  |  |  |  |  |  |  |  |  |  |  |  | 6 years |  |  |  |  |  |  |  |  |  |
Total upfront and milestone payments made to collaborative partner |  |  |  |  |  |  |  |  |  |  |  |  | $ 100.0 |  |  |  |  |  |  |  |  |  |
Prepaid research and discovery services |  |  |  |  |  |  |  |  |  |  |  |  | $ 25.0 |  |  |  |  |  |  |  |  |  |
License Fee |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 70.0 |  |  |  |  |
Expected License Fee And Regulatory Milestone Payments |  |  | 130.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 130.0 |  |  |  |  |
Additional milestone payments for product candidate using a different modality |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 90.0 |  |  |  |  |
Additional milestone payment |  |  | 10.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10.0 |  |  |  |  |
Eisai |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Biogen's share of expense reflected within our consolidation statements of income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 50.5 | 40.4 | 29.1 |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  | $ 21.6 |  |  |  |  |  |  | 50.0 |  |  |  |  |
Total expense incurred by collaboration |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 95.1 | 84.1 | 57.5 |  |  |
Total upfront and milestone payments made to collaborative partner |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 100.0 |  |
Additional milestone payment |  |  | 1,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000.0 |  |  |  |  |
Milestone payment made during period |  |  |  |  |  |  |  |  |  |  | $ 35.0 |  |  |  |  |  |  |  |  |  |  |  |
AGTC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  | 48.1 |  |  |  |  |  |  |  |  |  | 26.5 | 54.5 |  |  |  |
Total upfront and milestone payments made to collaborative partner |  |  |  |  |  |  |  | 124.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Prepaid research and discovery services |  |  |  |  |  |  |  | 58.4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additional milestone payment |  |  | 1,100.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,100.0 |  |  |  |  |
Purchase of common stock |  |  |  |  |  |  |  | 30.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total licensing and other fees |  |  |  |  |  |  |  | $ 35.6 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development services |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6.5 |  |  |  |
Premium on equity investment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7.5 |  |  |  |
University of Pennsylvania |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 20.0 |  |  |  |  |  |
Prepaid research and development |  |  |  |  | $ 15.0 |  |  |  |  |  |  |  |  |  |  |  | $ 15.0 |  |  |  |  |  |
Future research and development commitment |  |  | 47.5 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 47.5 |  |  |  |  |
Potential future milestone payments commitment, approximately |  |  | 2,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,000.0 |  |  |  |  |
Sangamo BioSciences |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Biogen's share of expense reflected within our consolidation statements of income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 13.4 | 13.6 | 28.9 |  |  |
Total upfront and milestone payments made to collaborative partner |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 20.0 |  |
Additional milestone payment |  |  | $ 300.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 300.0 |  |  |  |  |
Mitsubishi Tanabe Pharma Corporation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  | $ 60.0 |  |  |  |  |  |  |  |  |  |  | 22.8 |  |  |  |  |
Other research and discovery |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10.3 | $ 9.7 | $ 40.0 |  |  |
Samsung Biosimilar Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  | $ 46.0 |  |  |  |  |  |  |  |  |  |  |
Collaboration profit (loss) sharing |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 15.1 |  |  |  |  |
Equity Method Investments, Expected Profit Share |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 50.00% |  |  |  |  |
RITUXAN |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of Co promotion Operating Profits first fifty million |  |  | 30.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 30.00% |  |  |  |  |
Percentage of share of Co promotion profits exceeding $50 million |  |  | 39.00% |  |  |  | 40.00% |  |  |  |  |  |  |  |  |  |  | 39.00% | 40.00% | 40.00% |  |  |
Percentage Of Co Promotion Operating Profits Greater Than First Fifty Million Option Two Sub Option One |  |  | 39.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 39.00% |  |  |  |  |
Percentage Of Co Promotion Operating Profits Greater Than First Fifty Million Option One |  |  | 40.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 40.00% |  |  |  |  |
GAZYVA |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of Co promotion Operating Profits first fifty million |  |  | 35.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 35.00% |  |  |  |  |
Co-promotion operating profit threshold for Rituxan in U S and Canada to determine share of co promotion operating profit prior to amendment |  |  | $ 50.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 50.0 |  |  |  |  |
Limit of gross sale of GAZYVA to be achieved in preceding 12 months under option one |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 150.0 |  |  |  |  |
Limit of gross sale of GAZYVA to be achieved in any 12 months under option one |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 150.0 |  |  |  |  |
Sales Trigger Gross Sales Threshold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 500.0 |  |  |  |  |
Percentage Of Co Promotion Operating Losses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 35.00% |  |  |  |  |
Percentage Of Co Promotion Operating Profits Greater Than First Fifty Million Option Two Sub Option One |  |  | 39.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 39.00% |  |  |  |  |
New Anti-CD20 | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future percentage of co-promotion operating profits |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 30.00% |  |  |  |  |
New Anti-CD20 | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future percentage of co-promotion operating profits |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 38.00% |  |  |  |  |
Ocrelizumab |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Reduction in royalty rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 50.00% |  |  |  |  |
Period of collaboration agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 11 years |  |  |  |  |
Ocrelizumab | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future royalties percentage to be received on sale of ocrelizumab |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 13.50% |  |  |  |  |
Ocrelizumab | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future royalties percentage to be received on sale of ocrelizumab |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 24.00% |  |  |  |  |
ZINBRYTA |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue on sales in the rest of world for RITUXAN |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 7.8 | $ 0.0 | $ 0.0 |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 16.0 |  |  |  |
ZINBRYTA | AbbVie |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Biogen's share of expense reflected within our consolidation statements of income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 24.3 | 60.8 | 67.4 |  |  |
ELOCTATE |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue on sales in the rest of world for RITUXAN |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 513.2 | 319.7 | 58.4 |  |  |
ELOCTATE | Swedish Orphan Biovitrum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 144.0 |  |  |  |  |
ALPROLIX | Swedish Orphan Biovitrum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 123.0 |  |  |  |  |
SPINRAZA |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue on sales in the rest of world for RITUXAN |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4.6 | 0.0 | 0.0 |  |  |
SPINRAZA | Ionis Pharmaceuticals, Inc. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Biogen's share of expense reflected within our consolidation statements of income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 257.8 | 74.9 | 27.7 |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 29.0 |  | 35.3 | 42.8 | 57.3 |  |  |
Estimated additional payments upon achievement of development and commercial milestones. |  |  | $ 90.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 90.0 |  |  |  |  |
SOD1 | Ionis Pharmaceuticals, Inc. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10.0 |  |  |  |
DMPK | Ionis Pharmaceuticals, Inc. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Biogen's share of expense reflected within our consolidation statements of income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.1 | 9.0 | 10.9 |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 12.0 |  |  |  |  |  |  |  |
Additional milestone payment |  |  |  |  |  |  | $ 4.2 |  |  |  |  |  |  |  | $ 59.0 |  |  |  | 4.2 |  |  |  |
Lead programs | AGTC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5.0 |  |  |  |
Additional milestone payment |  |  | 472.5 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 472.5 |  |  |  |  |
Discovery programs | AGTC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additional milestone payment |  |  | 592.5 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 592.5 |  |  |  |  |
Samsung Biosimilar Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other revenues from external customers |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 20.2 | 62.9 | 58.5 |  |  |
Additional milestone payment |  |  | $ 25.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 25.0 |  |  |  |  |
Investments By Third Party In Joint Venture As Per Agreement. |  | $ 250.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | ₩ 280.5 |
Joint Venture Owner Ship Percentage By Third Party. |  | 85.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity Method Investments |  | $ 45.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | ₩ 49.5 |
Percentage of equity interest to the portion of total capital stock |  | 15.00% | 6.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6.50% |  |  |  | 15.00% |
Equity Method Investment Ownership Percentage Maximum |  | 49.90% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue | Swedish Orphan Biovitrum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Biogen effective royalty rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.14 |  |  |  |  |
Cost of sales | Swedish Orphan Biovitrum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Biogen effective royalty rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.11 |  |  |  |  |
Research and development | AbbVie |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total expense incurred by collaboration |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 48.6 | 113.8 | 117.8 |  |  |
Research and development | Eisai |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount recorded to reflect fair value of options granted |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 17.7 |  |
Selling, general and administrative | ZINBRYTA | AbbVie |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Biogen's share of expense reflected within our consolidation statements of income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 22.0 |  |  |  |  |
U.S |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue on sales in the rest of world for RITUXAN |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7,050.4 | 6,545.8 | 5,566.7 |  |  |
Other revenues from external customers |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 224.7 | 142.0 | 212.6 |  |  |
U.S | Roche Group - Genentech |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Biogen's share of pre-tax profits in the U.S. for RITUXAN and GAZYVA, including the reimbursement of selling and development expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,249.5 | 1,269.8 | 1,117.1 |  |  |
U.S | AbbVie |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other revenues from external customers |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 21.9 |  |  |  |  |
Outside the U.S | RITUXAN | Roche Group - Genentech |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue on sales in the rest of world for RITUXAN |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 65.0 | 69.4 | 78.3 |  |  |
Outside the U.S | Ocrelizumab |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future royalties percentage to be received on sale of ocrelizumab |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.00% |  |  |  |  |
Europe |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue on sales in the rest of world for RITUXAN | [1] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,533.5 | 1,497.6 | 1,383.9 |  |  |
Other revenues from external customers | [1] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 70.0 | $ 29.6 | $ 31.6 |  |  |
Europe | AbbVie |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaboration profit (loss) sharing |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4.9 |  |  |  |  |
Acquired and in-licensed rights and patents | ZINBRYTA |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net change in acquired and in-licensed rights and patents |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 32.0 |  |  |  |  |
Acquired and in-licensed rights and patents | ALPROLIX |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net change in acquired and in-licensed rights and patents |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 26.5 |  |  |  |  |
Milestone payment made during period |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 20.0 |  |  |  |  |
Acquired and in-licensed rights and patents | SPINRAZA |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net change in acquired and in-licensed rights and patents |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 60.0 |  |  |  |  |
Acquired and in-licensed rights and patents | Biosimilars |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net change in acquired and in-licensed rights and patents |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 50.0 |  |  |  |  |
[1] | Represents amounts related to Europe less those attributable to Germany.

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