Note 10 - Significant Customers	9 Months Ended
Sep. 30, 2021
Notes to Financial Statements
Concentration Risk Disclosure [Text Block]	*10.* Significant Customers The Company had no customers that represented over 10% of revenue during either of the nine-month periods ended September 30, 2021 or 2020. The Company had one customer that represented 11% of the total accounts receivable balance as of September 30, 2021. The Company had no customers that represented greater than 10% of the total accounts receivable balance as of December 31, 2020.

The entire disclosure for any concentrations existing at the date of the financial statements that make an entity vulnerable to a reasonably possible, near-term, severe impact. This disclosure informs financial statement users about the general nature of the risk associated with the concentration, and may indicate the percentage of concentration risk as of the balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

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