Note 2 - Accounting Policies - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Numerator for basic and diluted earnings per share	$ 1,328,000	$ 194,000
Denominator for basic and diluted earnings per share – weighted-average shares (in shares)	6,297,000	6,044,000
Effect of dilutive securities Employee stock options and restricted stock (in shares)	6,000	15,000
Denominator for diluted earnings per share – adjusted weighted-average shares (in shares)	6,303,000	6,059,000
Earnings per common share- basic (in dollars per share)	$ 0.21	$ 0.03
Earnings per common share- diluted (in dollars per share)	$ 0.21	$ 0.03