Amortization and Impairment of Acquired Intangible Assets

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Indefinite lived intangible assets useful life.

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No definition available.

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- Definition

Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
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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.

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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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in remainder of current fiscal year.

+ References

No definition available.

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- Definition

Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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- Definition

Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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- Definition

Amount before accumulated amortization of intangible assets, excluding goodwill.

+ References

No definition available.

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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.

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Intangible Assets and Goodwill (Details) - USD ($)	3 Months Ended			6 Months Ended
Intangible Assets and Goodwill (Details) - USD ($)	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2021	Jun. 30, 2021	Jun. 30, 2020	Mar. 31, 2021
Intangible assets
Contingent consideration impairment	$ (300,000)		$ (10,000,000.0)		$ 33,500,000	$ (5,500,000)
Total intangible assets, gross	7,637,700,000	$ 8,220,800,000			7,637,700,000
Accumulated Amortization	(5,252,700,000)	(5,136,500,000)			(5,252,700,000)
Intangible assets, net	2,385,000,000.0	3,084,300,000			2,385,000,000.0
Amortization and impairment of acquired intangible assets	604,100,000		61,500,000		702,200,000	133,000,000.0
Expected future amortization expense, 2019 (remaining three months)	110,000,000.0				110,000,000.0
Expected future amortization expense, 2020	215,000,000.0				215,000,000.0
Expected future amortization expense, 2021	215,000,000.0				215,000,000.0
Expected future amortization expense, 2022	225,000,000.0				225,000,000.0
Expected future amortization expense, 2023	220,000,000.0				220,000,000.0
Expected future amortization expense, 2024	200,000,000.0				200,000,000.0
Impairment of intangible assets					585,900,000	0
Impairment of Intangible Assets (Excluding Goodwill)			0		0	$ 0
Out-licensed patents
Intangible assets
Cost	7,394,300,000	7,394,300,000			7,394,300,000
Net	2,141,600,000	2,257,800,000			2,141,600,000
Accumulated Amortization	(5,252,700,000)	(5,136,500,000)			$ (5,252,700,000)
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 \| Minimum
Intangible assets
Estimated life, (in years)					15 years
Developed technology \| Maximum
Intangible assets
Estimated life, (in years)					28 years
Acquired and in-licensed rights and patents \| Minimum
Intangible assets
Estimated life, (in years)					4 years
Acquired and in-licensed rights and patents \| Maximum
Intangible assets
Estimated life, (in years)					18 years
In Process Research and Development
Intangible assets
Indefinite lived intangible assets useful life					Indefinite until commercialization
Cost and Net	179,400,000	762,500,000			$ 179,400,000
Accumulated Amortization	0	0			$ 0
Trademarks and Trade Names
Intangible assets
Indefinite lived intangible assets useful life					Indefinite
Cost and Net	64,000,000.0	64,000,000.0			$ 64,000,000.0
Accumulated Amortization	0	0			0
Vixotrigine
Intangible assets
Amortization and impairment of acquired intangible assets	44,300,000		$ 0
TGN [Member] \| In Process Research and Development
Intangible assets
Cost and Net	136,000,000.0				136,000,000.0
BIIB111 \| In Process Research and Development
Intangible assets
Cost and Net	15,000,000.0				15,000,000.0		$ 365,000,000.0
BIIB111 \| Nightstar
Intangible assets
Impairment of intangible assets	350,000,000.0	$ 115,000,000.0			350,000,000.0
BIIB112 \| In Process Research and Development
Intangible assets
Cost and Net	28,400,000				28,400,000		$ 220,000,000.0
BIIB112 \| Nightstar
Intangible assets
Impairment of intangible assets	$ 191,600,000				$ 191,600,000
BIIB111 and BIIB112 \| Nightstar \| Forecast
Intangible assets
Impairment of intangible assets				$ 30,000,000.0