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Upfront license fee payment related to license and collaboration agreement

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Percentage of development costs responsible for, under the license and collaboration agreement

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- Definition

Potential Future Milestone Payment Under License and Collaboration Agreement

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Potential Future Milestone Payment, Tiered Royalty Payment

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- Definition

Purchase Price of Goods Less Specified Amount, Maximum Percentage

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- Definition

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.

+ 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)
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-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26626-111562

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- Definition

Balance held at close of period in number of shares.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
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- 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://www.xbrl.org/2003/role/presentationRef
-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

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-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

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Price of a single share of a number of saleable stocks of a company.

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No definition available.

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- 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.

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Collaborative Arrangements - Collaborative Arrangements Narrative (Details) shares in Millions, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2016 USD ($) shares	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Mar. 31, 2016 € / shares
Variable Interest Entity [Line Items]
Available-for-sale Securities, Equity Securities, Noncurrent		$ 0	$ 428
Collaboration Arrangement Investment in Counterparty Ownership Percentage	14.75%
Research and development expenses		$ 3,734	$ 5,098	$ 3,014
Percentage of Costs Responsible			80.00%
Janssen Pharmaceuticals [Member]
Variable Interest Entity [Line Items]
Purchase price of goods less specified amount, maximum percentage			30.00%
Galapagos [Member]
Variable Interest Entity [Line Items]
License Fee Payment			$ 300
Available-for-sale Securities, Equity Securities, Noncurrent	$ 425
Share Price \| € / shares					€ 58
Investment Owned, Balance, Shares \| shares	6.8
Research and development expenses	$ 68		$ 60
Percentage of Costs Responsible			20.00%
Galapagos [Member] \| Minimum [Member]
Variable Interest Entity [Line Items]
Potential Future Milestone Payment, Tiered Royalty Payment			20.00%
Galapagos [Member] \| Maximum [Member]
Variable Interest Entity [Line Items]
Potential Future Milestone Payment, Tiered Royalty Payment			30.00%
Development And Regulatory Milestones-Based [Member] \| Galapagos [Member]
Variable Interest Entity [Line Items]
Potential Future Milestone Payment			$ 755
Sales-Based Milestones [Member] \| Galapagos [Member]
Variable Interest Entity [Line Items]
Potential Future Milestone Payment			$ 600