Number of major customers.

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- Definition

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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- Definition

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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- Definition

The amount of cash as of the balance sheet date that is not insured by the Federal Deposit Insurance Corporation.

+ References

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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Note 3 - Concentration of Credit Risk (Details Textual)	3 Months Ended		6 Months Ended		12 Months Ended
Note 3 - Concentration of Credit Risk (Details Textual)	Jun. 30, 2021 USD ($)	Jun. 30, 2020	Jun. 30, 2021 USD ($)	Jun. 30, 2020	Dec. 31, 2020 USD ($)
Cash and Cash Equivalents, at Carrying Value, Ending Balance	$ 5,387,896		$ 5,387,896		$ 7,699,335
Cash Equivalents, at Carrying Value, Total	1,000,000.0		1,000,000.0		1,000,000.0
Cash, Uninsured Amount	$ 3,203,000		$ 3,203,000		$ 5,822,000
Customer Concentration Risk [Member] \| Revenue Benchmark [Member]
Number Of Major Customers	3	2	1	1
Customer Concentration Risk [Member] \| Revenue Benchmark [Member] \| Customer A [Member]
Concentration Risk, Percentage	17.30%	42.20%	18.00%	37.00%
Customer Concentration Risk [Member] \| Revenue Benchmark [Member] \| Customer B [Member]
Concentration Risk, Percentage	12.90%	10.00%
Customer Concentration Risk [Member] \| Revenue Benchmark [Member] \| Customer C [Member]
Concentration Risk, Percentage	11.20%
Customer Concentration Risk [Member] \| Accounts Receivable [Member]
Number Of Major Customers			2		2
Customer Concentration Risk [Member] \| Accounts Receivable [Member] \| Two Customers [Member]
Concentration Risk, Percentage			20.20%		35.00%