2.2.0.7falseNew Accounting Pronouncements0220 - Disclosure - New Accounting Pronouncementstruefalsefalsefalse1USDfalsefalseUSDStandardhttp://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$20us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalsefalse00falsefalsefalsexbrli:stringItemTypestringNo definition available.false31us-gaap_ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlockus-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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<b><font style="font-family: 'Times New Roman', Times">20.  </font></b>
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<b><font style="font-family: 'Times New Roman', Times">New
Accounting Pronouncements</font></b>
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From time to time, new accounting pronouncements are issued by
the Financial Accounting Standards Board (FASB) or other
standard setting bodies that are adopted by the Company as of
the specified effective date. Unless otherwise discussed, we
believe that the impact of recently issued standards that are
not yet effective will not have a material impact on our
financial position or results of operations upon adoption.
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In April 2010, the FASB issued ASU
<font style="white-space: nowrap">No. 2010-17,</font>
<i>Revenue Recognition — Milestone Method </i>(ASU
<font style="white-space: nowrap">2010-017).</font>
ASU <font style="white-space: nowrap">2010-017</font>
provides guidance in applying the milestone method of revenue
recognition to research or development arrangements. Under this
guidance management may recognize revenue contingent upon the
achievement of a milestone in its entirety, in the period in
which the milestone is achieved, only if the milestone meets all
the criteria within the guidance to be considered substantive.
This ASU is effective on a prospective basis for research and
development milestones achieved in fiscal years, beginning on or
after June 15, 2010, which for Biogen Idec means fiscal
2011. Early adoption is permitted; however, adoption of this
guidance as of a date other than January 1, 2011 will
require us to apply this guidance retrospectively effective as
of January 1, 2010 and will require disclosure of the
effect of this guidance as applied to all previously reported
interim periods in the fiscal year of adoption. As we plan to
implement
<font style="white-space: nowrap">ASU 2010-17</font>
prospectively, the effect of this guidance will be limited to
future transactions. We do not expect adoption of this standard
to have a material impact on our financial position or results
of operations as we have no material research and development
arrangements which will be accounted for under the milestone
method.
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<!-- Begin Block Tagged Notefalsefalsefalseus-types:textBlockItemTypetextblockRepresents disclosure of any changes in an accounting principle, including a change from one generally accepted accounting principle to another generally accepted accounting principle when there are two or more generally accepted accounting principles that apply or when the accounting principle formerly used is no longer generally accepted. Also disclose any change in the method of applying an accounting principle, or any change in an accounting principle required by a new pronouncement in the unusual instance that a new pronouncement does not include specific transition provisions.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 154
-Paragraph 2, 17, 18
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 28
-Paragraph 23, 24
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 01
-Paragraph b
-Subparagraph 6
-Article 10
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