Note 4 - Basic and Diluted Net Income (Loss) Per Share - Basic and Diluted Weighted Average Common Shares Outstanding (Details) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Weighted average common shares outstanding, basic (in shares)	5,610	5,539	5,600	5,538
Dilutive common equivalent shares (in shares)	0	88	0	83
Weighted average common shares outstanding, diluted (in shares)	5,610	5,627	5,600	5,621