2.2.0.7falseRevenue Recognition (Policies)0403 - Disclosure - Revenue Recognition (Policies)truefalsefalsefalse1USDfalsefalseUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0PureStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDEPSDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0$20biib_RevenueRecognitionPoliciesAbstractbiibfalsenadurationRevenue recognition.falsefalsefalsefalsefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalsefalse00falsefalsefalsexbrli:stringItemTypestringRevenue recognition.false31us-gaap_RevenueRecognitionPolicyTextBlockus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabelfalse1falsefalsefalsefalse00<!--DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd" -->
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During the third quarter of 2010, we elected to early adopt
Accounting Standards Update (ASU)
<font style="white-space: nowrap">No. 2009-13,</font>
<i>Multiple-Deliverable Revenue Arrangements </i>(ASU
<font style="white-space: nowrap">2009-13).</font>
<font style="white-space: nowrap">ASU 2009-13,</font>
amends existing revenue recognition accounting pronouncements
and provides accounting principles and application guidance on
whether multiple deliverables exist, how the arrangement should
be separated, and the consideration allocated. This guidance
eliminates the requirement to establish the fair value of
undelivered products and services and instead provides for
separate revenue recognition based upon management’s
estimate of the selling price for an undelivered item when there
is no other means to determine the fair value of that
undelivered item. Previous accounting principles required that
the fair value of the undelivered item be the price of the item
either sold in a separate transaction between unrelated third
parties or the price charged for each item when the item is sold
separately by the vendor. The early adoption of this standard
requires the disclosure of the effect of this guidance as
applied to all previously reported interim periods in the fiscal
year of adoption. Our adoption of this standard did not have a
material impact our financial position or results of
operations as through the third quarter of 2010, we had not
recorded any revenue in accordance with revenue recognition
rules for multiple deliverables as described in ASU
<font style="white-space: nowrap">2009-13</font> or
its predecessor pronouncements.
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<!-- Begin Block Taggedfalsefalsefalseus-types:textBlockItemTypetextblockDescribes an entity's accounting policy for revenue recognition. If the entity has different policies for different types of revenue transactions, the policy for each material type of transaction should be disclosed. If a sales transaction has multiple element arrangements (for example, delivery of multiple products, services or the rights to use assets) the disclosure may indicate the accounting policy for each unit of accounting as well as how units of accounting are determined and valued. The disclosure may encompass important judgment as to appropriateness of principles related to recognition of revenue. The disclosure also may indicate the entity's treatment of any unearned or deferred revenue that arises from the transaction.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 13
-Section B
-Paragraph Question 1
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 22
-Paragraph 8, 12, 13
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