Note 8 - Share Option and Equity Incentive Plan - Expense Recognized During the Year Related to Share-based Compensation Transactions (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share-based compensation	$ 1,015	$ 1,506	$ 3,761	$ 4,266
Continuing Operations [Member]
Share-based compensation	948	1,452	3,550	4,129
Discontinued Operations [Member]
Share-based compensation	67	54	211	137
Cost of Revenue [Member]
Share-based compensation	38	42	161	125
Research and Development Expense [Member]
Share-based compensation	201	180	581	461
Selling and Marketing Expense [Member]
Share-based compensation	137	484	774	1,327
General and Administrative Expense [Member]
Share-based compensation	$ 572	$ 746	$ 2,034	$ 2,216

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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=109197908&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=109197908&loc=d3e5070-113901

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Balance Type:	debit
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