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Collaborative and Other Relationships (Details 4) (Portola Pharmaceuticals, USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Portola Pharmaceuticals |  |  |
Summary of activity related to collaboration with Portola Pharmaceuticals, Inc. |  |  |
Total expense incurred by collaboration | $ 1.6 | $ 18.8 | $ 1.1
Biogen Idec's share of expense reflected within our consolidation statements of income | $ 1.6 | $ 14.2 | $ 0.9

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- Definition Biogen Idec's share of expense reflected within our consolidated statements of income. + References No definition available. + Details
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- Details
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