Indefinite lived intangible assets useful life.

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- Definition

Milestone Payments Made During Period.

+ References

No definition available.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

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- Definition

Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
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- Definition

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
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-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Amount of increase (decrease) in carrying value of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

No definition available.

+ Details

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- Definition

Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ 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 (a,h)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount before accumulated amortization of intangible assets, excluding goodwill.

+ References

No definition available.

+ Details

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- Definition

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 1
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- References

No definition available.

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No definition available.

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Intangible Assets and Goodwill (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Intangible assets
Total intangible assets, gross	$ 7,712.5		$ 7,712.5		$ 7,646.3
Accumulated Amortization	(3,842.6)		(3,842.6)		(3,561.2)
Intangible assets, net	3,869.9		3,869.9		4,085.1
Intangible Assets and Goodwill (Textual) [Abstract]
Amortization of acquired intangible assets	99.7	$ 98.1	281.4	$ 286.0
Accumulated impairment losses related to goodwill	0.0		0.0
Expected future amortization expense, 2016 (remaining three months)	92.8		92.8
Expected future amortization expense, 2017	347.8		347.8
Expected future amortization expense, 2018	321.4		321.4
Expected future amortization expense, 2019	301.9		301.9
Expected future amortization expense, 2020	265.6		265.6
Expected future amortization expense, 2021	247.7		247.7
Out-licensed patents
Intangible assets
Cost	543.3		543.3		543.3
Accumulated Amortization	(519.4)		(519.4)		(506.0)
Net	23.9		$ 23.9		37.3
Out-licensed patents \| Minimum
Intangible assets
Estimated life, (in years)			13 years
Out-licensed patents \| Maximum
Intangible assets
Estimated life, (in years)			23 years
Developed technology
Intangible assets
Cost	3,005.3		$ 3,005.3		3,005.3
Accumulated Amortization	(2,619.8)		(2,619.8)		(2,552.9)
Net	385.5		$ 385.5		452.4
Developed technology \| Minimum
Intangible assets
Estimated life, (in years)			15 years
Developed technology \| Maximum
Intangible assets
Estimated life, (in years)			23 years
Developed technology \| AVONEX
Intangible assets
Net	377.8		$ 377.8
Acquired and in-licensed rights and patents
Intangible assets
Cost	3,420.2		3,420.2		3,303.2
Accumulated Amortization	(703.4)		(703.4)		(502.3)
Net	2,716.8		$ 2,716.8		2,800.9
Acquired and in-licensed rights and patents \| Minimum
Intangible assets
Estimated life, (in years)			6 years
Acquired and in-licensed rights and patents \| Maximum
Intangible assets
Estimated life, (in years)			18 years
Acquired and in-licensed rights and patents \| Biosimilars
Intangible assets
Increase in acquired and in-licensed rights and patents	25.0		$ 50.0
Acquired and in-licensed rights and patents \| ZINBRYTA
Intangible assets
Increase in acquired and in-licensed rights and patents			32.0
Acquired and in-licensed rights and patents \| ALPROLIX
Intangible assets
Increase in acquired and in-licensed rights and patents			26.5
Contingent payment made during the period			20.0
Deferred tax liability	6.5		$ 6.5
In-process research and development
Intangible assets
Indefinite lived intangible assets useful life			Indefinite until commercialization
Cost and Net	679.7		$ 679.7		730.5
Accumulated Amortization	0.0		$ 0.0		0.0
Trademarks and trade names
Intangible assets
Indefinite lived intangible assets useful life			Indefinite
Cost and Net	64.0		$ 64.0		64.0
Accumulated Amortization	0.0		0.0		$ 0.0
TYSABRI product \| Acquired and in-licensed rights and patents
Intangible assets
Net	$ 2,559.9		$ 2,559.9