Note 5 - Allowance for Doubtful Accounts - Activity in Accounts Receivable Allowance from Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Balance at beginning of period	$ 47	$ 473
Bad debt expense	0	9
Write-offs	0	(229)
Other adjustments	(30)	(206)
Balance at end of period	$ 17	$ 47