XML 173 R118.htm IDEA: XBRL DOCUMENT
v3.6.0.2

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 |  |  |  |  |

X
- Definition Accrued expenses on funding commitment related to clinical research. + References No definition available. + Details
Name: | biib_AccruedExpensesOnFundingCommitmentRelatedToClinicalResearch
Namespace Prefix: | biib_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Commitments And Contingencies. + References No definition available. + Details
Name: | biib_CommitmentsAndContingenciesTextualAbstract
Namespace Prefix: | biib_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Cumulative sales level + References No definition available. + Details
Name: | biib_CumulativeSalesLevel
Namespace Prefix: | biib_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Future contingent payment for annual worldwide net sales that exceed $2.0 billion + References No definition available. + Details
Name: | biib_FutureContingentPaymentForAnnualWorldwideNetSalesThatExceed20Billion
Namespace Prefix: | biib_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Future contingent payment for annual worldwide net sales up to $2.0 billion + References No definition available. + Details
Name: | biib_FutureContingentPaymentForAnnualWorldwideNetSalesUpTo20Billion
Namespace Prefix: | biib_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Future contingent payment threshold + References No definition available. + Details
Name: | biib_FutureContingentPaymentThreshold
Namespace Prefix: | biib_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Potential future milestone payments commitment to third party approximately. + References No definition available. + Details
Name: | biib_PotentialFutureMilestonePaymentsCommitmentToThirdPartyApproximately
Namespace Prefix: | biib_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- 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. + Details
Name: | us-gaap_BusinessAcquisitionLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- 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 + Details
Name: | us-gaap_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- 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 + Details
Name: | us-gaap_GoodwillAcquiredDuringPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- 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. + Details
Name: | us-gaap_LeaseAndRentalExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- 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) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LiabilityForUncertainTaxPositionsCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of judgment or settlement awarded to (against) the entity in respect of litigation. + References No definition available. + Details
Name: | us-gaap_LitigationSettlementAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees. + References No definition available. + Details
Name: | us-gaap_LitigationSettlementExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- 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
Name: | us-gaap_OtherCommitment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- 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 + Details
Name: | us-gaap_PaymentsToAcquireBusinessesGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=biib_TysabriProductMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=biib_FumapharmAgMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | biib_FacilityLocationAxis=biib_SolothurnMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ProductOrServiceAxis=biib_TecfideraMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | biib_CumulativeSalesLevelAxis=biib_TenbillionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | biib_CumulativeSalesLevelAxis=biib_SevenbillionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | biib_CumulativeSalesLevelAxis=biib_EightbillionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | biib_CumulativeSalesLevelAxis=biib_NinebillionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | biib_CumulativeSalesLevelAxis=biib_ElevenbillionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | biib_CumulativeSalesLevelAxis=biib_OneBillionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | biib_CumulativeSalesLevelAxis=biib_EachAdditionalOneBillionUpToTwentyBillionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | biib_CumulativeSalesLevelAxis=biib_ThreeBillionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementGeographicalAxis=country_US
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementGeographicalAxis=us-gaap_EuropeanUnionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | biib_FutureContingentMilestoneTypesAxis=biib_DevelopmentMilestonesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | biib_FutureContingentMilestoneTypesAxis=biib_RegulatoryMilestonesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | biib_FutureContingentMilestoneTypesAxis=biib_CommercialMilestonesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |