XML 105 R74.htm IDEA: XBRL DOCUMENT
v3.21.1

Collaborative and Other Relationships - Collaborations (Details) $ / shares in Units, shares in Millions, $ in Millions | 1 Months Ended | 3 Months Ended |
--- | --- | --- | ---
Nov. 30, 2020 USD ($) $ / shares shares | Feb. 29, 2020 USD ($) $ / shares shares | Mar. 31, 2021 USD ($) product $ / shares | Mar. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Jan. 31, 2020 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |
Loss on equity method investment |  |  | $ (18.2) | $ (16.8) |  |
Eisai |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |
Number of product candidates | product |  |  | 2 |  |  |
Expense Incurred By Collaboration |  |  | $ 55.5 | 43.5 |  |
Expense reflected within statements of income |  |  | $ 27.7 | 21.8 |  |
Percentage of future development costs related to Eisai |  |  | 45.00% |  |  |
Loss on research and development contracts terminated with Eisai |  |  |  |  | $ 45.0 |
Loss on equity method investment |  |  | $ 33.8 |  |  |
Denali Therapeutics |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |
Global Licensing Collaboration Agreement, Amount, Shares Purchased |  |  | $ 465.0 |  |  |
Global Licensing Collaboration Agreement, Shares Purchased Per Share | $ / shares |  |  | $ 34.94 |  |  |
Upfront and milestone payments made to collaborative partner |  |  | $ 560.0 |  |  |
Global Licensing Collaboration Agreement, Research, Development, Regulatory and Commercial Milestone Payments |  |  | 1,100.0 |  |  |
Research and development expense |  |  | $ 41.3 |  |  |
Samsung Bioepis |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |
Upfront and milestone payments made to collaborative partner |  |  |  | 100.0 |  |
Collaboration agreement term |  |  | 5 years |  |  |
Research and development expense |  |  |  | 63.0 |  |
Prepaid research and development expenses |  |  |  |  |  | $ 37.0
Sage Therapeutics Inc. |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |
Global Licensing Collaboration Agreement, Amount, Shares Purchased | $ 650.0 |  |  |  |  |
Global Licensing Collaboration Agreement, Shares, Purchased | shares | 6.2 |  |  |  |  |
Upfront and milestone payments made to collaborative partner | $ 875.0 |  |  |  |  |
Global Licensing Collaboration Agreement, Research, Development, Regulatory and Commercial Milestone Payments | 1,600.0 |  |  |  |  |
Research and development expense | $ 209.0 |  |  |  |  |
Global Licensing Collaboration Agreement, Purchase Price Per Share | $ / shares | $ 104.14 |  |  |  |  |
Sangamo Therapeutics, Inc. Agreement |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |
Global Licensing Collaboration Agreement, Amount, Shares Purchased |  | $ 225.0 |  |  |  |
Global Licensing Collaboration Agreement, Shares, Purchased | shares |  | 24.0 |  |  |  |
Global Licensing Collaboration Agreement, Shares Purchased Per Share | $ / shares |  | $ 9.21 |  |  |  |
Upfront and milestone payments made to collaborative partner |  | $ 125.0 |  |  |  |
Global Licensing Collaboration Agreement, Research, Development, Regulatory and Commercial Milestone Payments |  | 2,400.0 |  |  |  |
Global Licensing Collaboration Agreement, Payment, Selection of Targets |  | 80.0 |  |  |  |
Global Licensing Collaboration Agreement, Payment, Achievement of First Commercial Sale Milestones |  | 1,900.0 |  |  |  |
Global Licensing Collaboration Agreement, Payment, Achievement of Specific Sales Based Milestones |  | 380.0 |  |  |  |
Research and development expense |  | $ 83.0 |  |  |  |
Term of collaboration agreement |  |  | 5 years |  |  |
Research and development | Eisai | Aducanumab |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |
Expense incurred by the collaboration |  |  | $ 47.0 | 19.1 |  |
Expense reflected within statements of income |  |  | 25.8 | 10.5 |  |
Research and development | UCB Pharma S.A. [Member] |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |
Expense incurred by the collaboration |  |  | 16.9 | 19.0 |  |
Expense reflected within statements of income |  |  | 8.4 | 9.5 |  |
Selling, general and administrative | Eisai | BAN2401 and Elenbecestat |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |
Expense incurred by the collaboration |  |  | 5.7 | 4.9 |  |
Expense reflected within statements of income |  |  | 2.9 | 2.4 |  |
Selling, general and administrative | Eisai | Aducanumab |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |
Expense incurred by the collaboration |  |  | 111.8 | 22.7 |  |
Expense reflected within statements of income |  |  | $ 60.3 | $ 12.3 |  |

X
- Definition Collaboration Agreement Term + References No definition available. + Details
Name: | biib_CollaborationAgreementTerm
Namespace Prefix: | biib_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Total expense incurred by collaboration. + References No definition available. + Details
Name: | biib_ExpenseIncurredByCollaboration
Namespace Prefix: | biib_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Expense incurred by the collaboration + References No definition available. + Details
Name: | biib_Expenseincurredbythecollaboration
Namespace Prefix: | biib_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Expense reflected within statements of income + References No definition available. + Details
Name: | biib_Expensereflectedwithinstatementsofincome
Namespace Prefix: | biib_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Global Licensing Collaboration Agreement, Amount, Shares Purchased + References No definition available. + Details
Name: | biib_GlobalLicensingCollaborationAgreementAmountSharesPurchased
Namespace Prefix: | biib_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Global Licensing Collaboration Agreement, Payment, Achievement of First Commercial Sale Milestones + References No definition available. + Details
Name: | biib_GlobalLicensingCollaborationAgreementPaymentAchievementofFirstCommercialSaleMilestones
Namespace Prefix: | biib_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Global Licensing Collaboration Agreement, Payment, Achievement of Specific Sales Based Milestones + References No definition available. + Details
Name: | biib_GlobalLicensingCollaborationAgreementPaymentAchievementofSpecificSalesBasedMilestones
Namespace Prefix: | biib_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Global Licensing Collaboration Agreement, Payment, Selection of Targets + References No definition available. + Details
Name: | biib_GlobalLicensingCollaborationAgreementPaymentSelectionofTargets
Namespace Prefix: | biib_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Global Licensing Collaboration Agreement, Purchase Price Per Share + References No definition available. + Details
Name: | biib_GlobalLicensingCollaborationAgreementPurchasePricePerShare
Namespace Prefix: | biib_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Global Licensing Collaboration Agreement, Research, Development, Regulatory and Commercial Milestone Payments + References No definition available. + Details
Name: | biib_GlobalLicensingCollaborationAgreementResearchDevelopmentRegulatoryandCommercialMilestonePayments
Namespace Prefix: | biib_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Global Licensing Collaboration Agreement, Shares, Purchased + References No definition available. + Details
Name: | biib_GlobalLicensingCollaborationAgreementSharesPurchased
Namespace Prefix: | biib_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Global Licensing Collaboration Agreement, Shares Purchased Per Share + References No definition available. + Details
Name: | biib_GlobalLicensingCollaborationAgreementSharesPurchasedPerShare
Namespace Prefix: | biib_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of Product Candidates + References No definition available. + Details
Name: | biib_NumberOfProductCandidates
Namespace Prefix: | biib_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of future development costs related to Eisai + References No definition available. + Details
Name: | biib_PercentageoffuturedevelopmentcostsrelatedtoEisai
Namespace Prefix: | biib_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Term of collaboration agreement + References No definition available. + Details
Name: | biib_Termofcollaborationagreement
Namespace Prefix: | biib_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Total upfront and milestone payments made to collaborative partner. + References No definition available. + Details
Name: | biib_UpfrontAndMilestonePaymentsMadeToCollaborativePartner
Namespace Prefix: | biib_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of income (loss) for proportionate share of equity method investee's income (loss). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(12)) -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(10)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(13)(f)) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570 + Details
Name: | us-gaap_IncomeLossFromEquityMethodInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The loss recognized on termination of a contract. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 912 -SubTopic 275 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84167019&loc=d3e54681-109401 + Details
Name: | us-gaap_LossOnContractTermination
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets. + References No definition available. + Details
Name: | us-gaap_PrepaidExpenseAndOtherAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 985 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 730 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373 + Details
Name: | us-gaap_ResearchAndDevelopmentExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=biib_EisaiMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=biib_DenaliTherapeuticsIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=biib_SamsungBiosimilarAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=biib_SageTherapeuticsIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=biib_SangamoTherapeuticsInc.AgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementLocationAxis=us-gaap_ResearchAndDevelopmentExpenseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=biib_AducanumabMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=biib_UCBPharmaS.A.Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementLocationAxis=us-gaap_SellingGeneralAndAdministrativeExpensesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=biib_E2609andBAN2401Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |