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Acquisitions, Divestitures, Research Collaborations and License Agreements - Acquisitions Narrative (Detail) $ / shares in Units, shares in Thousands, € in Millions, $ in Millions, $ in Millions |  |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Jan. 16, 2020 USD ($) | Apr. 01, 2019 USD ($) | Dec. 31, 2020 USD ($) | Sep. 30, 2020 USD ($) $ / shares shares | Sep. 30, 2020 EUR (€) shares | Jul. 31, 2020 USD ($) | Jun. 30, 2020 USD ($) | May 31, 2020 USD ($) | Jul. 31, 2019 USD ($) | Apr. 30, 2019 USD ($) | Jun. 30, 2018 USD ($) | Jun. 30, 2018 AUD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  | $ 13,558.0 | $ 9,872.0 | $ 9,752.0
Goodwill |  |  | $ 20,238.0 |  |  |  |  |  |  |  |  |  | 20,238.0 | 19,425.0 | 18,253.0
Payments to acquire available for sale securities, equity |  |  |  |  |  |  |  |  |  |  |  |  | 1,000.0 | 0.0 | 0.0
Payments to acquire productive assets |  |  |  |  |  |  |  |  |  |  |  |  | 4,684.0 | 3,473.0 | 2,615.0
Contingent consideration |  |  | 841.0 |  |  |  |  |  |  |  |  |  | 841.0 | 767.0 | 788.0
IPR&D impairment charges |  |  |  |  |  |  |  |  |  |  |  |  |  | 172.0 | 152.0
Business combination, contingent consideration arrangements, change in amount of contingent consideration liability |  |  |  |  |  |  |  |  |  |  |  |  | (83.0) | (64.0) |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Premium on shares acquired |  |  |  |  |  |  |  |  |  |  |  |  | 16.0 |  |
Sentinel |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash paid for acquisition of business |  |  |  |  |  | $ 410.0 |  |  |  |  |  |  |  |  |
Sentinel | Products and product rights |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Finite-lived intangible assets acquired |  |  |  |  |  | 401.0 |  |  |  |  |  |  |  |  |
Inventories |  |  |  |  |  | $ 9.0 |  |  |  |  |  |  |  |  |
COVID-19 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  | 45.0 |  |
IPR&D impairment charges |  |  |  |  |  |  |  |  |  |  |  |  | 90.0 |  |
Business combination, contingent consideration arrangements, change in amount of contingent consideration liability |  |  |  |  |  |  |  |  |  |  |  |  | 45.0 |  |
Inventory and fixed assets write-offs |  |  |  |  |  |  |  |  |  |  |  |  | 260.0 |  |
Charges related to program discontinuation |  |  |  |  |  |  |  |  |  |  |  |  | 305.0 |  |
Seagen |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  | 616.0 |  |
Upfront and milestone payments |  |  |  | $ 600.0 |  |  |  |  |  |  |  |  |  |  |
Payments to acquire available for sale securities, equity |  |  |  | 1,000.0 |  |  |  |  |  |  |  |  |  |  |
Contingent payments collaborative arrangement |  |  |  | $ 2,600.0 |  |  |  |  |  |  |  |  |  |  |
Share Price (in dollars per share) | $ / shares |  |  |  | $ 200 |  |  |  |  |  |  |  |  |  |  |
Equity interests issued or issuable (in shares) | shares |  |  |  | 5,000 | 5,000 |  |  |  |  |  |  |  |  |  |
Seagen | Tukysa |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Upfront and milestone payments |  |  |  | $ 210.0 |  |  |  |  |  |  |  |  |  |  |
Seagen | Tukysa | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Royalty rate, percentage |  |  |  | 20.00% | 20.00% |  |  |  |  |  |  |  |  |  |
Seagen | Tukysa | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Royalty rate, percentage |  |  |  | 33.00% | 33.00% |  |  |  |  |  |  |  |  |  |
Sentinel | Products and product rights |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated useful life of intangible assets, acquired |  |  |  |  |  | 15 years |  |  |  |  |  |  |  |  |
IAVI |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Upfront and milestone payments |  |  |  |  |  |  |  | $ 6.5 |  |  |  |  |  |  |
OncoImmune |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash paid for acquisition of business |  |  | 423.0 |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  | 462.0 |  |
Payments to Acquire Investments |  |  | 50.0 |  |  |  |  |  |  |  |  |  |  |  |
Other assets and liabilities, net |  |  | (22.0) |  |  |  |  |  |  |  |  |  | (22.0) |  |
Premium on shares acquired |  |  | 17.0 |  |  |  |  |  |  |  |  |  |  |  |
Investments |  |  | $ 33.0 |  |  |  |  |  |  |  |  |  | $ 33.0 |  |
Equity method, ownership percentage |  |  | 20.00% |  |  |  |  |  |  |  |  |  | 20.00% |  |
OncoImmune | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Royalty rate, percentage |  |  | 10.00% |  |  |  |  |  |  |  |  |  |  |  |
OncoImmune | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Royalty rate, percentage |  |  | 20.00% |  |  |  |  |  |  |  |  |  |  |  |
VelosBio |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash paid for acquisition of business |  |  | $ 2,800.0 |  |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,700.0 |  |
Other assets and liabilities, net |  |  | 180.0 |  |  |  |  |  |  |  |  |  | 180.0 |  |
Dunboyne |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other assets and liabilities, net |  |  |  | $ 13.0 |  |  |  |  |  |  |  |  |  |  |
Payments to acquire productive assets |  |  |  | 302.0 | € 256 |  |  |  |  |  |  |  |  |  |
Property, plant and equipment |  |  |  | 289.0 |  |  |  |  |  |  |  |  |  |  |
Themis |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash paid for acquisition of business |  |  |  |  |  |  | $ 366.0 |  |  |  |  |  |  |  |
Potential future milestone payments, maximum |  |  | 450.0 |  |  |  | 740.0 |  |  |  |  |  | 450.0 |  |
Other assets and liabilities, net |  |  |  |  |  |  | (32.0) |  |  |  |  |  |  |  |
Goodwill |  |  |  |  |  |  | 230.0 |  |  |  |  |  |  |  |
In-process research and development (IPR&D) |  |  |  |  |  |  | 136.0 |  |  |  |  |  |  |  |
Cash and cash equivalents |  |  |  |  |  |  | 59.0 |  |  |  |  |  |  |  |
Contingent consideration |  |  |  |  |  |  | 97.0 |  |  |  |  |  |  |  |
Deferred tax assets |  |  |  |  |  |  | $ 70.0 |  |  |  |  |  |  |  |
Themis | COVID-19 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
IPR&D impairment charges |  |  |  |  |  |  |  |  |  |  |  |  | 90.0 |  |
Business combination, contingent consideration arrangements, change in amount of contingent consideration liability |  |  |  |  |  |  |  |  |  |  |  |  | 45.0 |  |
ArQule |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash paid for acquisition of business | $ 2,700.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred tax liabilities | 361.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other assets and liabilities, net | 34.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Goodwill | 512.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Transaction costs | 95.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
In-process research and development (IPR&D) | 2,280.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | 145.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation payments to settle equity awards attributable to precombination service | $ 138.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
ArQule | Measurement Input, Discount Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Present value discount rate | 0.125 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Peloton |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash paid for acquisition of business |  |  |  |  |  |  |  |  | $ 1,200.0 |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 993.0 |
Deferred tax liabilities |  |  |  |  |  |  |  |  | 52.0 |  |  |  |  |  |
Other assets and liabilities, net |  |  |  |  |  |  |  |  | 4.0 |  |  |  |  |  |
Cash and cash equivalents |  |  |  |  |  |  |  |  | 157.0 |  |  |  |  |  |
Antelliq |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash paid for acquisition of business |  | $ 2,300.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Debt assumed |  | 1,300.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred tax liabilities |  | 589.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Other assets and liabilities, net |  | (82.0) |  |  |  |  |  |  |  |  |  |  |  |  |
Goodwill |  | 1,376.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Transaction costs |  | 47.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents |  | 31.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Property, plant and equipment |  | 60.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Inventories |  | $ 93.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Antelliq | Measurement Input, Discount Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Present value discount rate |  | 0.115 |  |  |  |  |  |  |  |  |  |  |  |  |
Immune Design |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash paid for acquisition of business |  |  |  |  |  |  |  |  |  | $ 301.0 |  |  |  |  |
Other net assets |  |  |  |  |  |  |  |  |  | 42.0 |  |  |  |  |
Goodwill |  |  |  |  |  |  |  |  |  | 20.0 |  |  |  |  |
In-process research and development (IPR&D) |  |  |  |  |  |  |  |  |  | 156.0 |  |  |  |  |
Cash and cash equivalents |  |  |  |  |  |  |  |  |  | $ 83.0 |  |  |  |  |
Viralytics |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash paid for acquisition of business |  |  |  |  |  |  |  |  |  |  | $ 378.0 | $ 502 |  |  |
Other net assets |  |  |  |  |  |  |  |  |  |  | $ 34.0 |  |  |  |
Research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 344.0
Regulatory Milestones | Seagen | Tukysa |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent payments collaborative arrangement |  |  |  | 65.0 |  |  |  |  |  |  |  |  |  |  |
Regulatory Milestones | OncoImmune |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potential future milestone payments, maximum |  |  | 255.0 |  |  |  |  |  |  |  |  |  | 255.0 |  |
Regulatory Milestones | Themis |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potential future milestone payments, maximum |  |  | 196.0 |  |  |  |  |  |  |  |  |  | 196.0 |  |
Regulatory Milestones | Peloton |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potential future milestone payments, maximum |  |  |  |  |  |  |  |  | 50.0 |  |  |  |  |  |
Commercial Milestone | Peloton |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potential future milestone payments, maximum |  |  |  |  |  |  |  |  | 50.0 |  |  |  |  |  |
Sales-Based Milestones | Seagen |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent payments collaborative arrangement |  |  |  | 1,750.0 |  |  |  |  |  |  |  |  |  |  |
Sales-Based Milestones | Themis |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potential future milestone payments, maximum |  |  | 194.0 |  |  |  |  |  |  |  |  |  | 194.0 |  |
Sales-Based Milestones | Peloton |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potential future milestone payments, maximum |  |  |  |  |  |  |  |  | $ 1,050.0 |  |  |  |  |  |
Development Milestones | Seagen |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent payments collaborative arrangement |  |  |  | $ 850.0 |  |  |  |  |  |  |  |  |  |  |
Development Milestones | Themis |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions Divestitures Research Collaborations And License Agreements Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potential future milestone payments, maximum |  |  | $ 60.0 |  |  |  |  |  |  |  |  |  | $ 60.0 |  |

X
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