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Revenues Revenues from Anti-CD20 Therapeutic Programs (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2018 | Mar. 31, 2017
Disaggregation of Revenue [Line Items] |  |
Other revenues from anti-cd20 therapeutic programs | $ 2,523.5 | $ 2,380.1
Total revenues from anti-CD20 therapeutic programs | 443.2 | 340.6
Genentech |  |
Disaggregation of Revenue [Line Items] |  |
Biogen's share of pre-tax profits in the U.S. for RITUXAN and GAZYVA, including the reimbursement of selling and development expenses | 349.6 | 323.5
Other revenues from anti-cd20 therapeutic programs | 93.6 | 17.1
Total revenues from anti-CD20 therapeutic programs | $ 443.2 | $ 340.6

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- Definition Revenues from anti-CD20 therapeutic programs consists of our share of pre-tax co-promotion profits in the U.S.; reimbursement of selling and development expense in the U.S.; and revenue on sales of RITUXAN outside the U.S., which consist of our share of pre-tax co-promotion profits in Canada. + References No definition available. + Details
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- Definition Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts. + 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(a)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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