Note 13 - Concentrations of Credit Risk (Details Textual)	6 Months Ended
Jun. 30, 2019 USD ($)	Jun. 30, 2018	Dec. 31, 2018 USD ($)
Cash, Uninsured Amount	$ 701,000		$ 313,000
Distributor [Member]
Number of Customers	1
Distributor [Member] \| Revenue Benchmark [Member] \| Customer Concentration Risk [Member]
Concentration Risk, Percentage	59.00%	62.00%
Marketing Partner [Member]
Number of Customers	1
Marketing Partner [Member] \| Accounts Receivable [Member] \| Customer Concentration Risk [Member]
Concentration Risk, Percentage	53.00%	64.00%

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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