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Share-Based Payments (Tables) | 9 Months Ended
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Sep. 30, 2012
Disclosure of Compensation Related Costs, Share-based Payments [Abstract] |
Share-based compensation expense included in consolidated statements of income |
| For the Three Months Ended September 30, |  | For the Nine Months Ended September 30,
(In millions) | 2012 |  | 2011 |  | 2012 |  | 2011
Research and development | $ | 18.0 |  |  | $ | 14.2 |  |  | $ | 55.8 |  |  | $ | 46.4 |
Selling, general and administrative | 27.7 |  |  | 22.4 |  |  | 81.5 |  |  | 65.2 |
Restructuring charges | — |  |  | — |  |  | — |  |  | (0.6 | )
Subtotal | 45.7 |  |  | 36.6 |  |  | 137.3 |  |  | 111.0 |
Capitalized share-based compensation costs | (1.5 | ) |  | (1.3 | ) |  | (4.0 | ) |  | (3.3 | )
Share-based compensation expense included in total cost and expenses | 44.2 |  |  | 35.3 |  |  | 133.3 |  |  | 107.7 |
Income tax effect | (13.0 | ) |  | (10.0 | ) |  | (40.1 | ) |  | (33.0 | )
Share-based compensation expense included in net income attributable to Biogen Idec Inc. | $ | 31.2 |  |  | $ | 25.3 |  |  | $ | 93.2 |  |  | $ | 74.7 |
Summary of share-based compensation expense associated with each of our share-based compensating programs |
| For the Three Months Ended September 30, |  | For the Nine Months Ended September 30,
(In millions) | 2012 |  | 2011 |  | 2012 |  | 2011
Stock options | $ | 0.7 |  |  | $ | 1.8 |  |  | $ | 1.6 |  |  | $ | 4.5 |
Market stock units | 5.6 |  |  | 3.5 |  |  | 17.2 |  |  | 11.2 |
Time-vested restricted stock units | 21.4 |  |  | 22.0 |  |  | 69.5 |  |  | 68.2 |
Performance-vested restricted stock units settled in shares | — |  |  | 0.2 |  |  | 0.1 |  |  | 0.9 |
Cash settled performance shares | 16.4 |  |  | 6.2 |  |  | 45.1 |  |  | 21.7 |
Employee stock purchase plan | 1.6 |  |  | 2.9 |  |  | 3.8 |  |  | 4.5 |
Subtotal | 45.7 |  |  | 36.6 |  |  | 137.3 |  |  | 111.0 |
Capitalized share-based compensation costs | (1.5 | ) |  | (1.3 | ) |  | (4.0 | ) |  | (3.3 | )
Share-based compensation expense included in total cost and expenses | $ | 44.2 |  |  | $ | 35.3 |  |  | $ | 133.3 |  |  | $ | 107.7 |
Summary of equity grants to employees, officers and directors under our current stock plans |
| For the Nine Months Ended September 30,
| 2012 |  | 2011
Market stock units(a) | 312,000 |  |  | 393,000 |
Cash settled performance shares(b) | 327,000 |  |  | 490,000 |
Time-vested restricted stock units(c) | 902,000 |  |  | 1,352,000 |
Performance-vested restricted stock units(d) | — |  |  | 1,000 |
(a) | Market stock units (MSUs) granted during the nine months ended September 30, 2012 include approximately 39,000 and 41,000 MSUs issued in 2012 based upon the attainment of performance criteria set for 2011 and 2010, respectively, in relation to shares granted in those years. The remainder of MSUs granted during the nine months ended September 30, 2012 include awards granted in conjunction with our annual awards made in February 2012 and MSUs granted in conjunction with the hiring of employees. These grants reflect the target number of shares eligible to be earned at the time of grant.
MSUs granted during the nine months ended September 30, 2011, include approximately 26,000 MSUs issued in 2011 based upon the attainment of performance criteria set for 2010 in relation to shares granted in 2010. The remainder of MSUs granted during the nine months ended September 30, 2011 include awards granted in conjunction with our annual awards made in February 2011 and MSUs granted in conjunction with the hiring of employees. These grants reflect the target number of shares eligible to be earned at the time of grant.
(b) | Cash settled performance shares (CSPSs) granted during the nine months ended September 30, 2012 include approximately 68,000 CSPSs issued in 2012 based upon the attainment of performance criteria set for 2011 in relation to shares granted in 2011. The remainder of CSPSs granted during the nine months ended September 30, 2012 include awards granted in conjunction with our annual awards made in February 2012 and CSPSs granted in conjunction with the hiring of employees. These grants reflect the target number of shares eligible to be earned at the time of grant.
CSPSs granted during the nine months ended September 30, 2011, include approximately 95,000 CSPSs issued in 2011 based upon the attainment of performance criteria set for 2010 in relation to shares granted in 2010. The remainder of CSPSs granted during the nine months ended September 30, 2011 include awards granted in conjunction with our annual awards made in February 2011 and CSPSs granted in conjunction with the hiring of employees. These grants reflect the target number of shares eligible to be earned at the time of grant.
(c) | Time-vested restricted stock units (RSUs) granted during the nine months ended September 30, 2012 primarily represent RSUs granted in conjunction with our annual awards made in February 2012 and awards made in conjunction with the hiring of new employees. RSUs granted during the nine months ended September 30, 2012 also include approximately 24,000 RSUs granted to our Board of Directors.
RSUs granted during the nine months ended September 30, 2011 primarily represent RSUs granted in conjunction with our annual awards made in February 2011 and awards made in conjunction with the hiring of new employees. RSUs granted during the nine months ended September 30, 2011 also include approximately 35,000 RSUs granted to our Board of Directors.
(d) | Performance-vested restricted stock units (PVRSUs) granted during the nine months ended September 30, 2011 represent shares earned for performance criteria set for 2010 in relation to shares granted in 2010. No PVRSUs were granted during the nine months ended September 30, 2012.

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- Definition Tabular disclosure of the allocation of equity-based compensation costs to a given line item on the balance sheet and income statement for the period. This may include the reporting line for the costs and the amount capitalized and expensed. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph g(1) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 14 -Section F Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph 64 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 14.F) -URI http://asc.fasb.org/extlink&oid=6793087&loc=d3e301413-122809 + Details
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