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Collaborative and Other Relationships (Details Textual) $ in Millions, ₩ in Billions | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Feb. 29, 2012 USD ($) | Dec. 31, 2015 USD ($) | Sep. 30, 2015 USD ($) | Jun. 30, 2015 USD ($) | Mar. 31, 2015 USD ($) | Dec. 31, 2014 USD ($) | Sep. 30, 2014 USD ($) | Jun. 30, 2014 USD ($) | Mar. 31, 2014 USD ($) | Dec. 31, 2013 USD ($) | Sep. 30, 2013 USD ($) | Dec. 31, 2012 USD ($) | Jun. 30, 2012 USD ($) | Mar. 31, 2012 USD ($) | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($) | Dec. 31, 2013 USD ($) | Dec. 31, 2010 USD ($) | Dec. 31, 2015 KRW (₩) | Dec. 31, 2014 KRW (₩) | Feb. 29, 2012 KRW (₩) | Jan. 31, 2007
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue on sales in the rest of world for RITUXAN |  | $ 2,425.9 | $ 2,391.7 | $ 2,198.6 | $ 2,172.3 | $ 2,287.0 | $ 2,117.3 | $ 2,056.3 | $ 1,742.8 |  |  |  |  |  | $ 9,188.5 | $ 8,203.4 | $ 5,542.3 |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,012.8 | 1,893.4 | 1,444.1 |  |  |  |  |
Income (Loss) from Equity Method Investments |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (12.5) | (15.1) | (17.2) |  |  |  |  |
Other revenues from external customers |  | 79.5 | 49.0 | $ 55.6 | $ 52.0 | $ 49.2 | $ 103.4 | 61.9 | 90.1 |  |  |  |  |  | 236.1 | 304.5 | 263.9 |  |  |  |  |
Biogen Hemophilia |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock acquired in acquisition |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100.00%
Milestone Payments Made During Period |  |  |  |  |  |  |  | 20.0 |  |  |  |  |  |  |  |  |  | $ 40.0 |  |  |  |
Genentech |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue on sales in the rest of world for RITUXAN |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 41.2 |  |  |  |  |
Biogen's share of pre-tax profits in the U.S. for RITUXAN and GAZYVA, including the reimbursement of selling and development expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 8.5 |  |  |  |  |
Elan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Reimbursements of research and developments expense from Elan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 11.7 |  |  |  |  |
Reimbursements of selling general and administrative expenses from Elan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 20.6 |  |  |  |  |
Amount reflected in collaboration profit sharing line for collaboration |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 85.4 |  |  |  |  |
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 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 30.6 | 29.2 | 24.3 |  |  |  |  |
Swedish Orphan Biovitrum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consideration per product |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 10.0 |  |  |  |  |  |  |
Percentage of reimbursement expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 50.00% |  |  |  |  |  |  |
Percentage of development reimbursement expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100.00% |  |  |  |  |  |  |
Reimbursement cost achieving period |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6 years |  |  |  |  |  |  |
Time period for paying remaining balance due |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 90 days |  |  |  |  |  |  |
Term for revocation option right |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 18 months |  |  |  |  |  |  |
AbbVie |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 16.0 |  |  |  |  |  |  |
Biogen's share of expense reflected within our consolidation statements of income |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 60.8 | 67.4 | 71.0 |  |  |  |  |
Estimated additional payments upon achievement of development and commercial milestones. |  | 32.0 |  |  |  |  |  |  |  |  |  |  |  |  | 32.0 |  |  |  |  |  |  |
Ionis Pharmaceuticals |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  | $ 75.0 | $ 30.0 |  |  | 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) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  | 21.6 | 117.7 |  |  |  |  |  |  |  |  |  |  |  |  |
Biogen's share of expense reflected within our consolidation statements of income |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 40.4 | 29.1 | $ 0.0 |  |  |  |  |
Total upfront and milestone payments made to collaborative partner |  |  |  |  |  |  |  |  | 100.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Additional Milestone Payment |  | 1,000.0 |  |  |  |  |  |  |  |  |  |  |  |  | 1,000.0 |  |  |  |  |  |  |
Milestone Payments Made During Period |  |  |  |  |  |  |  | $ 35.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sangamo BioSciences |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Biogen's share of expense reflected within our consolidation statements of income |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 13.6 | 28.9 |  |  |  |  |  |
Total upfront and milestone payments made to collaborative partner |  |  |  |  |  |  |  |  | 20.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Additional Milestone Payment |  | 300.0 |  |  |  |  |  |  |  |  |  |  |  |  | 300.0 |  |  |  |  |  |  |
AGTC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  | 48.1 |  |  |  |  |  |  |  |  |  |  |  | 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 |  |  |  |  |  |  |
Mitsubishi Tanabe Pharma Corporation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  | 60.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additional Milestone Payment |  | $ 484.0 |  |  |  |  |  |  |  |  |  |  |  |  | 484.0 |  |  |  |  |  |  |
Other research and discovery |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 9.7 | $ 40.0 |  |  |  |  |  |
Samsung Biosimilar Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  | $ 46.0 |  |  |  |  |  |  |  |  |  |  |  |
Equity Method Investments, Expected Profit Share |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 50.00% |  |  |  |  |  |  |
RITUXAN |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Royalties Terms Of Collaboration Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10% and 12% on sales of RITUXAN outside the U.S. and Canada, with the royalty period lasting 11 years |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Period of collaboration agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 11 years |  |  |  |  |  |  |
Percentage of Co promotion Operating Profits first fifty million |  | 30.00% |  |  |  |  |  |  |  |  |  |  |  |  | 30.00% |  |  |  | 30.00% |  |  |
Percentage of share of Co promotion profits exceeding $50 million |  | 40.00% |  |  |  | 40.00% |  |  |  | 40.00% |  |  |  |  | 40.00% | 40.00% | 40.00% |  | 40.00% | 40.00% |  |
Royalty Period For Substantially All Remaining Royalty Bearing Sales Rest Of World |  |  |  |  |  |  |  |  |  |  |  |  |  |  | expire through 2012 |  |  |  |  |  |  |
Percentage Of Co Promotion Operating Profits Greater Than First Fifty Million Option Two Sub Option One |  | 39.00% |  |  |  |  |  |  |  |  |  |  |  |  | 39.00% |  |  |  | 39.00% |  |  |
Percentage Of Co Promotion Operating Profits Greater Than First Fifty Million Option One |  | 40.00% |  |  |  |  |  |  |  |  |  |  |  |  | 40.00% |  |  |  | 40.00% |  |  |
RITUXAN | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of royalties as per collaboration |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 12.00% |  |  |  |  |  |  |
RITUXAN | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of royalties as per collaboration |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10.00% |  |  |  |  |  |  |
GAZYVA |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of future development and commercialization expenses payable related to GAZYVA |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 35.00% |  |  |  |  |  |  |
Percentage of Co promotion Operating Profits first fifty million |  | 35.00% |  |  |  |  |  |  |  |  |  |  |  |  | 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% |  |  |  | 39.00% |  |  |
New Anti-CD20 | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future percentage of co-promotion operating profits |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 38.00% |  |  |  |  |  |  |
New Anti-CD20 | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future percentage of co-promotion operating profits |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 30.00% |  |  |  |  |  |  |
ELOCTATE |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue on sales in the rest of world for RITUXAN |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 319.7 | $ 58.4 | $ 0.0 |  |  |  |  |
ELOCTATE | Swedish Orphan Biovitrum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 200.0 |  |  |  |  |  |  |
ALPROLIX | Swedish Orphan Biovitrum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 175.0 |  |  |  |  |  |  |
Ocrelizumab |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Reduction in royalty rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 50.00% |  |  |  |  |  |  |
Ocrelizumab | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future royalties percentage to be received on sale of ocrelizumab |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 24.00% |  |  |  |  |  |  |
Ocrelizumab | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future royalties percentage to be received on sale of ocrelizumab |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 13.50% |  |  |  |  |  |  |
SOD1 | Ionis Pharmaceuticals |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 10.0 |  |  |  |  |  |  |
DMPK | Ionis Pharmaceuticals |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  | $ 12.0 |  | 2.8 | 14.0 | 10.0 |  |  |  |  |
Biogen's share of expense reflected within our consolidation statements of income |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 9.0 | 10.9 | 11.2 |  |  |  |  |
License Fee |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 70.0 |  |  |  |  |  |  |
Expected License Fee And Regulatory Milestone Payments |  | $ 130.0 |  |  |  |  |  |  |  |  |  |  |  |  | 130.0 |  |  |  |  |  |  |
Additional Milestone Payment |  | 4.2 |  |  |  |  |  |  |  |  |  |  | $ 59.0 |  | 4.2 |  |  |  |  |  |  |
SMNRx | Ionis Pharmaceuticals |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 29.0 | 42.8 | 57.3 |  |  |  |  |  |
Biogen's share of expense reflected within our consolidation statements of income |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 74.9 | 27.7 | 13.6 |  |  |  |  |
Estimated additional payments upon achievement of development and commercial milestones. |  |  |  |  |  | $ 325.0 |  |  |  |  |  |  |  |  |  | 325.0 |  |  |  |  |  |
Expected License Fee And Regulatory Milestone Payments |  |  |  |  |  | 150.0 |  |  |  |  |  |  |  |  |  | 150.0 |  |  |  |  |  |
Additional Milestone Payment |  | 92.0 |  |  |  | 100.0 |  |  |  |  |  |  |  |  | 92.0 | 100.0 |  |  |  |  |  |
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) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additional Milestone Payment |  | 75.0 |  |  |  |  |  |  |  |  |  |  |  |  | 75.0 |  |  |  |  |  |  |
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 | $ 5.7 |  |  |  | $ 8.6 |  |  |  |  |  |  |  |  | $ 5.7 | 8.6 |  |  | ₩ 6.3 | ₩ 9.1 | ₩ 49.5 |
Percentage of equity interest to the portion of total capital stock | 15.00% | 9.00% |  |  |  |  |  |  |  |  |  |  |  |  | 9.00% |  |  |  | 9.00% |  | 15.00% |
Equity Method Investment Ownership Percentage Maximum | 49.90% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other revenues from external customers |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 62.9 | 58.5 | 43.1 |  |  |  |  |
Samsung Biosimilar Agreement | Biosimilars |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additional Milestone Payment |  | $ 25.0 |  |  |  |  |  |  |  |  |  |  |  |  | 25.0 |  |  |  |  |  |  |
New Anti-CD20 | Third Party Anti CD-20 | Roche Group - Genentech |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 25.7 |  |  |  |  |
Hoechst |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Decrease In Share Of Co Promotion Profits Due To Estimated Compensation Damages |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 49.7 |  |  |  |  |
Research and development | Eisai |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount recorded to reflect fair value of options granted |  |  |  |  |  |  |  |  | $ 17.7 |  |  |  |  |  |  |  |  |  |  |  |  |
Outside the U.S | AbbVie |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated additional payments upon achievement of development and commercial milestones. |  | 12.0 |  |  |  |  |  |  |  |  |  |  |  |  | 12.0 |  |  |  |  |  |  |
Outside the U.S | RITUXAN | Roche Group - Genentech |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue on sales in the rest of world for RITUXAN |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 69.4 | 78.3 | 38.7 |  |  |  |  |
Outside the U.S | Ocrelizumab |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future royalties percentage to be received on sale of ocrelizumab |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.00% |  |  |  |  |  |  |
U.S |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue on sales in the rest of world for RITUXAN |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 6,545.8 | 5,566.7 | 3,581.0 |  |  |  |  |
Other revenues from external customers |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 142.0 | 212.6 | 193.5 |  |  |  |  |
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 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,269.8 | $ 1,117.1 | $ 1,087.3 |  |  |  |  |
U.S | AbbVie |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative and Other Relationships (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated additional payments upon achievement of development and commercial milestones. |  | $ 20.0 |  |  |  |  |  |  |  |  |  |  |  |  | $ 20.0 |  |  |  |  |  |  |

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