Note 2 - Accounting Policies - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Numerator for basic and diluted earnings (loss) per share	$ 194,000	$ (7,058,000)
Denominator for basic and diluted earnings per share – weighted-average shares (in shares)	6,044,000	6,182,000
Effect of dilutive securities Employee stock options and restricted stock (in shares)	15,000	0
Denominator for diluted earnings per share – adjusted weighted-average shares (in shares)	6,059,000	6,182,000
Earnings (loss) per common share- basic (in dollars per share)	$ 0.03	$ (1.14)
Earnings (loss) per common share- diluted (in dollars per share)	$ 0.03	$ (1.14)