Note 1 - Summary of Operations and Significant Accounting Policies (Details Textual) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($) shares	Dec. 31, 2017 USD ($) shares
Research and Development Expense, Gross \| $	$ 4,905	$ 5,142
Customer Funded Research and Development Expense Included in Cost of Goods Sold \| $	397	405
Research and Development, Revenue \| $	$ 397	$ 405
Weighted Average Number Diluted Shares Outstanding Adjustment, Total	465,004
Number of Operating Segments	2
Employee Stock Option [Member]
Incremental Common Shares Attributable to Share-based Payment Arrangements, Total	1,127,837	1,035,711
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	448,250	824,500
Restricted Stock [Member]
Incremental Common Shares Attributable to Share-based Payment Arrangements, Total	17,500	330,676
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance		0
Customer Concentration Risk [Member] \| Sales Revenue, Net [Member]
Number of Major Customers	1	1
Customer Concentration Risk [Member] \| Sales Revenue, Net [Member] \| Large Defense Primary Contractor, 1 [Member]
Concentration Risk, Percentage	16.00%	18.00%

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The gross costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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