Note 3 - Summary of Significant Accounting Policies (Details Textual) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Accounts Receivable, after Allowance for Credit Loss, Total	$ 0	$ 0
Revenue from Contract with Customer, Including Assessed Tax
Weighted Average Number Diluted Shares Outstanding Adjustment, Total (in shares)	0	0
Hardware [Member}
Revenue from Contract with Customer, Including Assessed Tax	$ 0	$ 0
Software [Member]
Revenue from Contract with Customer, Including Assessed Tax	0	0
Digital Watermarketing Software Usage [Mmember]
Revenue from Contract with Customer, Including Assessed Tax	$ 0	$ 0