Note 10 - Share Option and Equity Incentive Plan - Expense Recognized During the Year Related to Share-based Compensation Transactions (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Share-based compensation	$ 845	$ 1,824
Continuing Operations [Member]
Share-based compensation	845	1,760
Discontinued Operations [Member]
Share-based compensation		64
Cost of Revenue [Member]
Share-based compensation	4	66
Research and Development Expense [Member]
Share-based compensation	(18)	218
Selling and Marketing Expense [Member]
Share-based compensation	224	567
General and Administrative Expense [Member]
Share-based compensation	$ 635	$ 909

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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