Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Topic 805
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- Definition

Value of input used to measure contingent consideration liability from business combination.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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- Definition

Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.

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Note 12 - Subsequent Event (Details Textual) $ in Thousands		3 Months Ended		6 Months Ended
Note 12 - Subsequent Event (Details Textual) $ in Thousands	Jul. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Business Combination, Contingent Consideration, Liability, Noncurrent		$ 18,900		$ 18,900		$ 16,800
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability		$ 1,300	$ 700	$ 2,100	$ 2,600
Subsequent Event [Member]
Business Combination, Contingent Consideration, Liability, Noncurrent	$ 19,800
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability	$ 900
AZEDRA Commercialization [Member] \| Measurement Input, Probability of Success [Member]
Business Combination, Contingent Consideration, Liability, Measurement Input		0.81		0.81		0.72
AZEDRA Commercialization [Member] \| Measurement Input, Probability of Success [Member] \| Subsequent Event [Member]
Business Combination, Contingent Consideration, Liability, Measurement Input	0.9