Accrued expenses on funding commitment related to clinical research.

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- Definition

Commitments And Contingencies.

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No definition available.

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- Definition

Cumulative sales level

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No definition available.

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- Definition

Future contingent payment for annual worldwide net sales that exceed $2.0 billion

+ References

No definition available.

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- Definition

Future contingent payment for annual worldwide net sales up to $2.0 billion

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No definition available.

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- Definition

Future contingent payment threshold

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No definition available.

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- Definition

Potential future milestone payments commitment to third party approximately.

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No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

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- Definition

Amount recognized for uncertainty in income taxes classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
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- Definition

Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

+ References

No definition available.

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- Definition

Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

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No definition available.

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- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ 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=66902209&loc=d3e3213-108585

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Commitments and Contingencies (Details Textual) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2006	Jun. 30, 2013	Apr. 02, 2013
Business Acquisition [Line Items]
Litigation settlement and license agreement amount	$ 1,250.0
TECFIDERA litigation settlement and license charges	454.8	$ 0.0	$ 0.0
Maximum contingent consideration in the form of development and approval milestones	1,200.0
Increase to goodwill	1,026.9	908.1
Potential future milestone payments commitment, approximately	3,100.0
Cancellable future commitments	500.0
Commitments And Contingencies (Textual)
Accrued expenses	21.0
Liabilities associated with uncertain tax positions	47.8
Lease rent expense which terminates at various dates through 2028	68.7	68.6	$ 62.4
TYSABRI
Business Acquisition [Line Items]
Future contingent payment for annual worldwide net sales up to $2.0 billion						18.00%
Future contingent payment threshold						$ 2,000.0
Future contingent payment for annual worldwide net sales that exceed $2.0 billion						25.00%
Fumapharm AG
Business Acquisition [Line Items]
Amount paid in cash				$ 220.0
Solothurn
Business Acquisition [Line Items]
Cancellable future commitments	176.3
TECFIDERA \| Fumapharm AG
Business Acquisition [Line Items]
Maximum contingent consideration in the form of development and approval milestones					$ 15.0
Increase to goodwill	1,200.0	$ 900.0
Ten billion \| TECFIDERA \| Fumapharm AG
Business Acquisition [Line Items]
Increase to goodwill	1,200.0
Cumulative sales level	10,000.0
Seven billion \| TECFIDERA \| Fumapharm AG
Business Acquisition [Line Items]
Cumulative sales level	7,000.0
Eight billion \| TECFIDERA \| Fumapharm AG
Business Acquisition [Line Items]
Cumulative sales level	8,000.0
Nine billion \| TECFIDERA \| Fumapharm AG
Business Acquisition [Line Items]
Cumulative sales level	9,000.0
Eleven billion \| TECFIDERA \| Fumapharm AG
Business Acquisition [Line Items]
Increase to goodwill	300.0
Cumulative sales level	11,000.0
One billion \| TECFIDERA \| Fumapharm AG
Business Acquisition [Line Items]
Cumulative sales level	1,000.0
Each additional one billion up to twenty billion \| TECFIDERA \| Fumapharm AG
Business Acquisition [Line Items]
Increase to goodwill	300.0
Cumulative sales level	20,000.0
Three billion \| TECFIDERA \| Fumapharm AG
Business Acquisition [Line Items]
Cumulative sales level	3,000.0
U.S
Business Acquisition [Line Items]
TECFIDERA litigation settlement and license charges	656.3
European Union
Business Acquisition [Line Items]
TECFIDERA litigation settlement and license charges	138.9
Development Milestones [Member]
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately	500.0
Regulatory Milestones [Member]
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately	800.0
Commercial Milestones [Member]
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately	$ 1,800.0