Note 12 - Related-party Transactions (Details Textual) - Consensys Imaging Services [Member] - Field Engineers Services [Member] - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction, Expenses from Transactions with Related Party	$ 80,000	$ 84,000
Accounts Payable, Related Parties	$ 27,000	$ 12,000

Amount for accounts payable to related parties.

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