Note 7 - Shareholders' Equity - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Total stock-based compensation expense	$ 210	$ 105	$ 378	$ 320
Cost of Sales [Member] \| Edge to Cloud [Member]
Total stock-based compensation expense	9	20	24	24
Selling, General and Administrative Expenses [Member]
Total stock-based compensation expense	181	80	327	286
Research and Development Expense [Member]
Total stock-based compensation expense	$ 20	$ 5	$ 27	$ 10

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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