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Acquisitions (Details Textual) - USD ($) $ in Millions	3 Months Ended					12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Acquired in-process research and development						$ 112.5	$ 120.0	$ 0.0
Karyopharm
Business Acquisition [Line Items]
Acquired in-process research and development				$ 10.0
Estimated additional payments upon achievement of development and commercial milestones						207.0
Pfizer
Business Acquisition [Line Items]
Acquired in-process research and development			$ 75.0
Estimated additional payments upon achievement of development and commercial milestones						515.0
TMS
Business Acquisition [Line Items]
Acquired in-process research and development						18.0
Estimated additional payments upon achievement of development and commercial milestones						335.0
Research and development expense asset acquired			$ 4.0
AliveGen
Business Acquisition [Line Items]
Acquired in-process research and development		$ 27.5
Estimated additional payments upon achievement of development and commercial milestones						$ 535.0
Remedy Pharmaceutical
Business Acquisition [Line Items]
Acquired in-process research and development					$ 120.0
Development Milestones | Pfizer
Business Acquisition [Line Items]
Estimated additional payments upon achievement of development and commercial milestones	$ 10.0

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Estimated additional payments upon achievement of development and commercial milestones.

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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
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