Note 3 - Somerset Acquisition, Goodwill, In-Process Research and Development and Other Intangible Assets - Components of Finite-lived Intangible Assets (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Gross amount	$ 8,265
Accumulated amortization	2,042
Net carrying value	6,223
AZEDRA Product Rights [Member]
Gross amount	4,900
Accumulated amortization	992
Net carrying value	3,908
Somerset [Member]
Gross amount	1,245
Accumulated amortization	176
Net carrying value	1,069
EXINI Technology [Member]
Gross amount	2,120
Accumulated amortization	874
Net carrying value	$ 1,246

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
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