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Fair Value Measurements - Acquisition of CyDex (Details) - Cydex Pharmaceuticals, Inc - Contingent Consideration Classified as Equity	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Credit Derivatives [Line Items]
Revenue volatility (as a percent)	25.00%	25.00%
Average probability of commercialization (as a percent)	12.50%	12.50%
Market price of risk	0.029	0.029

X

- Definition

Average Probability of Commercialization

+ References

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- Definition

Fair Value Inputs, Sales Beta

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

+ 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 (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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