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Collaborative and Other Relationships (Details 1) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |  |  |  |  |  |  |
Product revenues, net | $ 3,307.0 | $ 3,077.8 | $ 3,078.4 | $ 2,810.7 | $ 2,872.0 | $ 2,955.8 | $ 2,894.2 | $ 2,726.8 | $ 12,273.9 | $ 11,448.8 | $ 10,763.8
Costs and expenses |  |  |  |  |  |  |  |  | 6,929.7 | 6,298.4 | $ 5,872.8
AbbVie |  |  |  |  |  |  |  |  |  |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |  |  |  |  |  |  |
Product revenues, net |  |  |  |  |  |  |  |  | 53.1 | 6.1 |
Costs and expenses |  |  |  |  |  |  |  |  | 92.6 | 50.0 |
Co-promotion profits and losses |  |  |  |  |  |  |  |  | 39.5 | 43.9 |
Biogen's share of co-promotion losses |  |  |  |  |  |  |  |  | $ 16.9 | $ 21.9 |

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- Definition Total costs of sales and operating expenses for the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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