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Commitments and Contingences (Details Textual) (USD $) | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2014 | Mar. 31, 2013 | Mar. 31, 2014 Fumapharm AG [Member] TECFIDERA [Member] | Mar. 31, 2014 One billion [Member] Fumapharm AG [Member] | Dec. 31, 2013 One billion [Member] Fumapharm AG [Member]
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |
Payment of contingent payment for acquisition | $ 25,000,000 | $ 0 | $ 25,000,000 |  |
Cumulative sales level |  |  |  | $ 1,000,000,000.0 | $ 1,000,000,000

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- Definition The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585 + Details
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