Note 2 - Summary of Significant Accounting Policies - Revenue From Unaffiliated Customers by Geographic Area (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Revenue	$ 6,426	$ 5,479
UNITED STATES
Revenue	3,701	2,537
Asia Pacific [Member]
Revenue	2,647	2,732
CANADA
Revenue	66	110
Europe And Middle East [Member]
Revenue	12	86
Latin America [Member]
Revenue	$ 0	$ 14

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details