XML 85 R51.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Fair Value Measurements (Details) (USD $) In Millions, unless otherwise specified | Sep. 30, 2014 | Jun. 30, 2014 | Dec. 31, 2013 | Sep. 30, 2013 | Jun. 30, 2013 | Dec. 31, 2012
--- | --- | --- | --- | --- | --- | ---
Assets: |  |  |  |  |  |
Marketable debt securities | $ 2,046.4 |  | $ 1,245.9 |  |  |
Fair Value, Measurements, Recurring |  |  |  |  |  |
Assets: |  |  |  |  |  |
Cash equivalents | 663.3 |  | 424.7 |  |  |
Derivative contracts | 42.9 |  | 3.8 |  |  |
Plan assets for deferred compensation | 35.2 |  | 22.7 |  |  |
Total | 2,805.2 |  | 1,730.2 |  |  |
Liabilities: |  |  |  |  |  |
Derivative contracts | 6.8 |  | 23.5 |  |  |
Contingent consideration obligations | 213.2 | 279.1 | 280.9 | 281.0 | 281.0 | 293.9
Total | 220.0 |  | 304.4 |  |  |
Fair Value, Measurements, Recurring | Corporate debt securities |  |  |  |  |  |
Assets: |  |  |  |  |  |
Marketable debt securities | 774.4 |  | 439.8 |  |  |
Fair Value, Measurements, Recurring | Government securities |  |  |  |  |  |
Assets: |  |  |  |  |  |
Marketable debt securities | 1,085.0 |  | 674.7 |  |  |
Fair Value, Measurements, Recurring | Mortgage and other asset backed securities |  |  |  |  |  |
Assets: |  |  |  |  |  |
Marketable debt securities | 187.0 |  | 131.4 |  |  |
Fair Value, Measurements, Recurring | Marketable equity securities |  |  |  |  |  |
Assets: |  |  |  |  |  |
Investments | 0.7 |  | 11.2 |  |  |
Fair Value, Measurements, Recurring | Venture capital investments |  |  |  |  |  |
Assets: |  |  |  |  |  |
Investments | 16.7 | 21.1 | 21.9 | 27.6 | 23.5 | 20.3
Quoted Prices in Active Markets, Level 1 | Fair Value, Measurements, Recurring |  |  |  |  |  |
Assets: |  |  |  |  |  |
Cash equivalents | 0 |  | 0 |  |  |
Derivative contracts | 0 |  | 0 |  |  |
Plan assets for deferred compensation | 0 |  | 0 |  |  |
Total | 0.7 |  | 11.2 |  |  |
Liabilities: |  |  |  |  |  |
Derivative contracts | 0 |  | 0 |  |  |
Contingent consideration obligations | 0 |  | 0 |  |  |
Total | 0 |  | 0 |  |  |
Quoted Prices in Active Markets, Level 1 | Fair Value, Measurements, Recurring | Corporate debt securities |  |  |  |  |  |
Assets: |  |  |  |  |  |
Marketable debt securities | 0 |  | 0 |  |  |
Quoted Prices in Active Markets, Level 1 | Fair Value, Measurements, Recurring | Government securities |  |  |  |  |  |
Assets: |  |  |  |  |  |
Marketable debt securities | 0 |  | 0 |  |  |
Quoted Prices in Active Markets, Level 1 | Fair Value, Measurements, Recurring | Mortgage and other asset backed securities |  |  |  |  |  |
Assets: |  |  |  |  |  |
Marketable debt securities | 0 |  | 0 |  |  |
Quoted Prices in Active Markets, Level 1 | Fair Value, Measurements, Recurring | Marketable equity securities |  |  |  |  |  |
Assets: |  |  |  |  |  |
Investments | 0.7 |  | 11.2 |  |  |
Quoted Prices in Active Markets, Level 1 | Fair Value, Measurements, Recurring | Venture capital investments |  |  |  |  |  |
Assets: |  |  |  |  |  |
Investments | 0 |  | 0 |  |  |
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring |  |  |  |  |  |
Assets: |  |  |  |  |  |
Cash equivalents | 663.3 |  | 424.7 |  |  |
Derivative contracts | 42.9 |  | 3.8 |  |  |
Plan assets for deferred compensation | 35.2 |  | 22.7 |  |  |
Total | 2,787.8 |  | 1,697.1 |  |  |
Liabilities: |  |  |  |  |  |
Derivative contracts | 6.8 |  | 23.5 |  |  |
Contingent consideration obligations | 0 |  | 0 |  |  |
Total | 6.8 |  | 23.5 |  |  |
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Corporate debt securities |  |  |  |  |  |
Assets: |  |  |  |  |  |
Marketable debt securities | 774.4 |  | 439.8 |  |  |
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Government securities |  |  |  |  |  |
Assets: |  |  |  |  |  |
Marketable debt securities | 1,085.0 |  | 674.7 |  |  |
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Mortgage and other asset backed securities |  |  |  |  |  |
Assets: |  |  |  |  |  |
Marketable debt securities | 187.0 |  | 131.4 |  |  |
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Marketable equity securities |  |  |  |  |  |
Assets: |  |  |  |  |  |
Investments | 0 |  | 0 |  |  |
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Venture capital investments |  |  |  |  |  |
Assets: |  |  |  |  |  |
Investments | 0 |  | 0 |  |  |
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring |  |  |  |  |  |
Assets: |  |  |  |  |  |
Cash equivalents | 0 |  | 0 |  |  |
Derivative contracts | 0 |  | 0 |  |  |
Plan assets for deferred compensation | 0 |  | 0 |  |  |
Total | 16.7 |  | 21.9 |  |  |
Liabilities: |  |  |  |  |  |
Derivative contracts | 0 |  | 0 |  |  |
Contingent consideration obligations | 213.2 |  | 280.9 |  |  |
Total | 213.2 |  | 280.9 |  |  |
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Corporate debt securities |  |  |  |  |  |
Assets: |  |  |  |  |  |
Marketable debt securities | 0 |  | 0 |  |  |
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Government securities |  |  |  |  |  |
Assets: |  |  |  |  |  |
Marketable debt securities | 0 |  | 0 |  |  |
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Mortgage and other asset backed securities |  |  |  |  |  |
Assets: |  |  |  |  |  |
Marketable debt securities | 0 |  | 0 |  |  |
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Marketable equity securities |  |  |  |  |  |
Assets: |  |  |  |  |  |
Investments | 0 |  | 0 |  |  |
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Venture capital investments |  |  |  |  |  |
Assets: |  |  |  |  |  |
Investments | $ 16.7 |  | $ 21.9 |  |  |

X
- Definition Fair values as of the balance sheet date of all assets of deferred compensation plans. + References No definition available. + Details
Name: | biib_PlanAssetsForDeferredCompensationFairValueDisclosure
Namespace Prefix: | biib_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_AssetsFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 + Details
Name: | us-gaap_AvailableForSaleSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of liability recognized arising from contingent consideration in a business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 25 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 35 -Paragraph 1 -Subparagraph b -URI http://asc.fasb.org/extlink&oid=6911338&loc=d3e6819-128478 + Details
Name: | us-gaap_BusinessCombinationContingentConsiderationLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash -URI http://asc.fasb.org/extlink&oid=6506951 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016 + Details
Name: | us-gaap_CashAndCashEquivalentsFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps. + References No definition available. + Details
Name: | us-gaap_ForeignCurrencyContractAssetFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into. + References No definition available. + Details
Name: | us-gaap_ForeignCurrencyContractsLiabilityFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 + Details
Name: | us-gaap_InvestmentsFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of financial and nonfinancial obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_LiabilitiesFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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