Note 11 - Business Segment and Geographic Financial Data - Geographic Segment Financial Data (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Revenues	$ 4,957	$ 7,287
Assets	49,446		$ 50,388
UNITED STATES
Revenues	3,595	5,981
Assets	45,744		46,487
Non-US [Member]
Revenues	1,362	$ 1,306
Assets	$ 3,702		$ 3,901

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