beatandraise : Equity Research with AI and ChatGPT on SEC Edgar

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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 16 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 22 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 13, 19 false 6 Amortized Cost 2 us-gaap_AvailableForSaleSecuritiesAmortizedCost us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 752900000 752900000 false false false 2 false false false false 0 0 false false false 3 false true false false 752900000 752900000 false false false 4 false false false false 0 0 false false false 5 false true false false 1860500000 1860500000 false false false xbrli:monetaryItemType monetary This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any. 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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 7 -Footnote 2 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 20 -Subparagraph b false 13 Due after five years, Estimated Fair Value 2 biib_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveYearsFairValue biib false debit instant This item represents the fair value of debt securities, which are expected to mature after five years from the balance sheet... false false false false false false false false false false false totallabel false 1 false true false false 43700000 43700000 false false false 2 false false false false 0 0 false false false 3 false true false false 43700000 43700000 false false false 4 false false false false 0 0 false false false 5 false true false false 210200000 210200000 false false false xbrli:monetaryItemType monetary This item represents the fair value of debt securities, which are expected to mature after five years from the balance sheet date and which are categorized neither as held-to-maturity nor trading securities. No authoritative reference available. true 14 Due after five years, Amortized Cost 2 biib_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveYearsAmortizedCost biib false debit instant This item represents debt securities, at cost, net of adjustments made for accretion, amortization, other-than-temporary... false false false false false false false false false false false totallabel false 1 false true false false 43400000 43400000 false false false 2 false false false false 0 0 false false false 3 false true false false 43400000 43400000 false false false 4 false false false false 0 0 false false false 5 false true false false 207600000 207600000 false false false xbrli:monetaryItemType monetary This item represents debt securities, at cost, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any, which are expected to mature after five years from the balance sheet date and which are categorized neither as held-to-maturity nor trading securities. No authoritative reference available. true 15 Total Fair Value 2 biib_AvailableForSalesSecuritiesDebtMaturitiesFairValue biib false debit instant Total of debt securities categorized neither as held-to-maturity nor trading. Such securities are reported at fair value;... false false false false false false false false false false false totallabel false 1 false true false false 757800000 757800000 false false false 2 false false false false 0 0 false false false 3 false true false false 757800000 757800000 false false false 4 false false false false 0 0 false false false 5 false true false false 1875900000 1875900000 false false false xbrli:monetaryItemType monetary Total of debt securities categorized neither as held-to-maturity nor trading. Such securities are reported at fair value; unrealized gains and losses of such securities are excluded from earnings and included in other comprehensive income, a separate component of shareholders' equity, unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain or loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis. No authoritative reference available. true 16 Total Amortized Cost 2 us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCost us-gaap true debit instant No definition available. false false false false false false false false false false false totallabel false 1 false true false false 752900000 752900000 false false false 2 false false false false 0 0 false false false 3 false true false false 752900000 752900000 false false false 4 false false false false 0 0 false false false 5 false true false false 1860500000 1860500000 false false false xbrli:monetaryItemType monetary This item represents the total of all debt securities grouped by maturity dates, at cost, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any, which are classified neither as held-to-maturity nor trading securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 7 -Footnote 2 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 20 true 17 Proceeds from Marketable Securities, excluding Strategic Investments 2 biib_ProceedsFromMarketableSecuritiesExcludingStrategicInvestmentsAbstract biib false na duration Proceeds From Marketable Securities Excluding Strategic Investments Abstract. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false xbrli:stringItemType string Proceeds From Marketable Securities Excluding Strategic Investments Abstract. false 18 Proceeds from maturities and sales 2 us-gaap_ProceedsFromSaleAndMaturityOfMarketableSecurities us-gaap true debit duration No definition available. false false false false false false false false false false false terselabel false 1 false true false false 487800000 487800000 false false false 2 false true false false 696500000 696500000 false false false 3 false true false false 2490363000 2490363000 false false false 4 false true false false 2334093000 2334093000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (trading, held-to-maturity, or available-for-sale) during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 15 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 16 -Subparagraph b Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 16 -Subparagraph a false 19 Realized gains 2 us-gaap_AvailableForSaleSecuritiesGrossRealizedGains us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 5000000 5000000 false false false 2 false true false false 3100000 3100000 false false false 3 false true false false 18100000 18100000 false false false 4 false true false false 17000000 17000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. 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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 21 -Subparagraph a false 21 Financial Instruments (Textuals) [Abstract] 2 biib_FinancialInstrumentsTextualsAbstract biib false na duration Financial Instruments. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false xbrli:stringItemType string Financial Instruments. false 22 Original maturities of commercial paper and short-term debt securities 2 us-gaap_DebtInstrumentMaturityDateDescription us-gaap true na duration No definition available. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 less than 90 days false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false xbrli:stringItemType string Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 2, 4 false 23 Federal Deposit Insurance Corporation guaranteed senior notes issued under the Temporary Liquidity Guarantee Program 2 biib_FederalDepositInsuranceCorporationGuaranteedSeniorNotesIssuedUnderTemporaryLiquidityGuaranteeProgram biib false debit instant Debt securities guaranteed by Federal Deposit Insurance Corporation under the Temporary Liquidity Guarantee Program. false false false false false false false false false false false verboselabel false 1 false true false false 127200000 127200000 false false false 2 false false false false 0 0 false false false 3 false true false false 127200000 127200000 false false false 4 false false false false 0 0 false false false 5 false true false false 298800000 298800000 false false false xbrli:monetaryItemType monetary Debt securities guaranteed by Federal Deposit Insurance Corporation under the Temporary Liquidity Guarantee Program. No authoritative reference available. false 24 Fair and carrying values of commercial paper including accrued interest 2 us-gaap_CommercialPaperAtCarryingValue us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 148500000 148500000 false false false 2 false false false false 0 0 false false false 3 false true false false 148500000 148500000 false false false 4 false false false false 0 0 false false false 5 false true false false 76900000 76900000 false false false xbrli:monetaryItemType monetary Unsecured short-term debt instrument issued by corporations which are 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. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 8, 9 false 25 Fair and carrying values of short-term debt securities 2 us-gaap_OtherCashEquivalentsAtCarryingValue us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 385800000 385800000 false false false 2 false false false false 0 0 false false false 3 false true false false 385800000 385800000 false false false 4 false false false false 0 0 false false false 5 false true false false 399500000 399500000 false false false xbrli:monetaryItemType monetary Other (not elsewhere specified in the taxonomy) 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. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 8, 9 false 26 Other-than-temporary impairment of available-for-sale securities primarily related to mortgage and asset backed securities, when lacking the ability and intent to hold the securities to recovery 2 biib_ChargesRelatedToMortgageAndAssetBackedSecuritiesIntentToHoldSecuritiesToRecovery biib false debit duration Charges related to mortgage and asset backed securities, intent to hold the securities to recovery. false false false false false false false false false false false verboselabel false 1 false true false false 2800000 2800000 false false false 2 false true false false 500000 500000 false false false 3 false true false false 19800000 19800000 false false false 4 false true false false 6500000 6500000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Charges related to mortgage and asset backed securities, intent to hold the securities to recovery. No authoritative reference available. false 27 Other-than-temporary impairment of available-for-sale securities primarily related to marketable debt securities 2 biib_ChargesRelatedToMarketableDebtSecurities biib false credit duration Charges related to marketable debt securities. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false true false false 3600000 3600000 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Charges related to marketable debt securities. No authoritative reference available. false 28 Average maturity of marketable securities, months 2 biib_AverageMaturityOfMarketableSecurities biib false na instant Average maturity of marketable securities. false false false false false false false false false false false verboselabel false 1 false true false false 13 13 false false false 2 false false false false 0 0 false false false 3 false true false false 13 13 false false false 4 false false false false 0 0 false false false 5 false true false false 15 15 false false false xbrli:integerItemType integer Average maturity of marketable securities. No authoritative reference available. false 29 Corporate debt securities Current [Member] 0 na true na na No definition available. false true false false false false false false false false false http://biogenidec.com/role/financialinstrumentsdetails false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false false 6 USD true false false false Corporate debt securities Current [Member] us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis xbrldi http://xbrl.org/2006/xbrldi biib_CorporateDebtSecuritiesCurrentMember us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 7 USD true false false false Corporate debt securities Current [Member] us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis xbrldi http://xbrl.org/2006/xbrldi biib_CorporateDebtSecuritiesCurrentMember us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ na No definition available. No authoritative reference available. false 30 Marketable Securities including Strategic Investments 2 us-gaap_AvailableForSaleSecuritiesAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 31 Fair Value 2 biib_AvailableForSaleDebtSecuritiesFairValue biib false debit instant Total of debt securities categorized neither as held-to-maturity nor trading. Such securities are reported at fair value;... false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false true false false 55300000 55300000 false false false 4 false false false false 0 0 false false false 5 false true false false 177200000 177200000 false false false xbrli:monetaryItemType monetary Total of debt securities categorized neither as held-to-maturity nor trading. Such securities are reported at fair value; unrealized gains and losses of such securities are excluded from earnings and included in other comprehensive income, a separate component of shareholders' equity, unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain or loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis. No authoritative reference available. false 32 Gross Unrealized Gains 2 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false true false false 100000 100000 false false false 4 false false false false 0 0 false false false 5 false true false false 1500000 1500000 false false false xbrli:monetaryItemType monetary This item represents the gross unrealized gains for securities which are categorized neither as held-to-maturity nor trading securities. Such gross unrealized gains are the excess of the fair value of the Available-for-sale Securities over their carrying value as of the reporting date. Such gross unrealized gains are included in other comprehensive income in the statement of shareholders' equity, unless the Available-for-sale Security is designated as a hedge. All or a portion of the unrealized holding gain of an available-for-sale security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge. 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Such gross unrealized losses are the excess of the carrying value of the Available-for-sale Securities over their fair value as of the reporting date. Such gross unrealized losses are included in other comprehensive income in the statement of shareholders' equity, unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis. 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Such gross unrealized gains are the excess of the fair value of the Available-for-sale Securities over their carrying value as of the reporting date. Such gross unrealized gains are included in other comprehensive income in the statement of shareholders' equity, unless the Available-for-sale Security is designated as a hedge. All or a portion of the unrealized holding gain of an available-for-sale security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge. 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Such gross unrealized losses are the excess of the carrying value of the Available-for-sale Securities over their fair value as of the reporting date. Such gross unrealized losses are included in other comprehensive income in the statement of shareholders' equity, unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 16 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 22 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 13, 19 false 174 Amortized Cost 2 us-gaap_AvailableForSaleSecuritiesAmortizedCost us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false true false false 55200000 55200000 false false false 4 false false false false 0 0 false false false 5 false true false false 231700000 231700000 false false false xbrli:monetaryItemType monetary This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 7 -Footnote 2 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 19 false 197 Other Strategic investments Non-Current [Member] 0 na true na na No definition available. false true false false false false false false false false false http://biogenidec.com/role/financialinstrumentsdetails false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false false 18 USD true false false false Other Strategic investments Non-Current [Member] us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis xbrldi http://xbrl.org/2006/xbrldi biib_OtherStrategicInvestmentsNonCurrentMember us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 19 USD true false false false Other Strategic investments Non-Current [Member] us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis xbrldi http://xbrl.org/2006/xbrldi biib_OtherStrategicInvestmentsNonCurrentMember us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ na No definition available. 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Such gross unrealized gains are the excess of the fair value of the Available-for-sale Securities over their carrying value as of the reporting date. Such gross unrealized gains are included in other comprehensive income in the statement of shareholders' equity, unless the Available-for-sale Security is designated as a hedge. All or a portion of the unrealized holding gain of an available-for-sale security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge. 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Such gross unrealized losses are the excess of the carrying value of the Available-for-sale Securities over their fair value as of the reporting date. Such gross unrealized losses are included in other comprehensive income in the statement of shareholders' equity, unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis. 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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 7 -Footnote 2 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 19 false 203 Strategic investments, non-current Fair Value 2 us-gaap_AvailableForSaleSecuritiesEquitySecuritiesNoncurrent us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 true true false false 36400000 36400000 false false false 4 false false false false 0 0 false false false 5 true true false false 5900000 5900000 false false false xbrli:monetaryItemType monetary This item represents equity securities categorized neither as held-to-maturity nor trading which are intended be sold more than one year from the balance sheet date or operating cycle, if longer. Equity securities represent ownership interests or the right to acquire ownership interests in corporations and other legal entities which ownership interest is represented by shares of common or preferred stock (which is not mandatorily redeemable or redeemable at the option of the holder), convertible securities, stock rights, or stock warrants. Unrealized gains and losses related to Available-for-sale securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain or loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis. 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