Note 2 - Summary of Significant Accounting Policies (Details Textual) shares in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($) shares	Dec. 31, 2021 USD ($) shares	Dec. 31, 2020 USD ($) shares
Cash Equivalents, at Carrying Value, Total	$ 0	$ 0
Depreciation, Depletion and Amortization, Nonproduction, Total	2,400	2,800	$ 2,700
Property, Plant and Equipment, Net, Ending Balance	4,573	$ 6,691
Finite-Lived Intangible Asset, Expected Amortization, Year One	62
Finite-Lived Intangible Asset, Expected Amortization, Year Two	62
Finite-Lived Intangible Asset, Expected Amortization, Year Three	62
Finite-Lived Intangible Asset, Expected Amortization, Year Four	62
Finite-Lived Intangible Asset, Expected Amortization, Year Five	62
Finite-Lived Intangible Asset, Expected Amortization, after Year Five	$ 109
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares) \| shares	508	574	588
Customer Concentration Risk [Member] \| Revenue Benchmark [Member]
Number of Major Customers	0	0	0
Customer Concentration Risk [Member] \| Accounts Receivable [Member]
Number of Major Customers	1	1	1
Customer Concentration Risk [Member] \| Accounts Receivable [Member] \| Customer One [Member]
Concentration Risk, Percentage	11.00%	12.00%
Patents [Member]
Amortization, Total	$ 62	$ 62	$ 62
Finite-Lived Intangible Asset, Useful Life (Year)	20 years
Legal Cost Capitalized	$ 1,100	1,100
Legal Cost Capitalized, Amortization	500	400
Legal Cost Capitalized, Net	600		700
Capitalized Software and Equipment [Member]
Property, Plant and Equipment, Net, Ending Balance	500
Software Development [Member]
Software Development Cost Capitalized	127	99
Amortization, Total	$ 282	$ 421	$ 293
Software Development [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Software Development [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	5 years

The amount of legal costs capitalized.

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Represents the number of major customers accounting for 10% or more of the specified concentration risk benchmark, which includes, but not limited to, sales revenue, accounts receivable, etc.

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The software development cost capitalized as of the balance sheet date.

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The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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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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Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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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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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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