The number of subsidiaries that are 100% owned by the reporting entity.

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Amount of allowance for credit loss on accounts receivable, classified as current.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of expense for amortization of capitalized computer software costs.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes 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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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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The amount of cash as of the balance sheet date that is not insured by the Federal Deposit Insurance Corporation.

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No definition available.

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- Definition

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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- Definition

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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No definition available.

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

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-SubTopic 20
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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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No definition available.

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The aggregate 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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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Note 2 - Summary of Significant Accounting Policies (Details Textual)	12 Months Ended
	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Number of Wholly Owned Subsidiaries	5
Capitalized Computer Software, Amortization	$ 142,480	$ 144,500
Amortization of Intangible Assets, Total	120,488	115,800
Research and Development Expense, Total	597,456	606,618
Cash and Cash Equivalents, at Carrying Value, Ending Balance	8,664,253	11,439,361	$ 14,210,909
Cash Equivalents, at Carrying Value, Total	2,100,000	7,500,000
Cash, Uninsured Amount	5,198,000	6,920,000
Accounts Receivable, Allowance for Credit Loss, Current	24,000	24,000
Accounting Standards Update 2016-02 [Member]
Operating Lease, Right-of-Use Asset	84,000
Cargo and Freight [Member]
Revenue from Contract with Customer, Excluding Assessed Tax, Total	$ 39,000	$ 61,200
Customer Concentration Risk [Member] \| Export Sales [Member]
Concentration Risk, Percentage	21.30%	9.90%
Three Customers [Member] \| Customer Concentration Risk [Member] \| Accounts Receivable [Member]
Concentration Risk, Percentage	61.00%
Two Customers [Member] \| Customer Concentration Risk [Member] \| Accounts Receivable [Member]
Concentration Risk, Percentage		42.00%
Two Customers [Member] \| Customer Concentration Risk [Member] \| Revenue Benchmark [Member]
Concentration Risk, Percentage	39.30%
One Customer [Member] \| Customer Concentration Risk [Member] \| Revenue Benchmark [Member]
Concentration Risk, Percentage	38.20%
Minimum [Member]
Finite-Lived Intangible Asset, Useful Life	5 years
Minimum [Member] \| Building and Building Improvements [Member]
Property, Plant and Equipment, Useful Life	5 years
Minimum [Member] \| Machinery and Equipment [Member]
Property, Plant and Equipment, Useful Life	5 years
Maximum [Member]
Finite-Lived Intangible Asset, Useful Life	20 years
Maximum [Member] \| Building and Building Improvements [Member]
Property, Plant and Equipment, Useful Life	39 years
Maximum [Member] \| Machinery and Equipment [Member]
Property, Plant and Equipment, Useful Life	8 years
Computer Software, Intangible Asset [Member] \| Minimum [Member]
Finite-Lived Intangible Asset, Useful Life	3 years
Computer Software, Intangible Asset [Member] \| Maximum [Member]
Finite-Lived Intangible Asset, Useful Life	5 years