Note 7 - Stock-based Compensation (Details Textual) - Incentive Compensation Plan [Member] - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Jun. 30, 2021
Common Stock, Capital Shares Reserved for Future Issuance (in shares)					2,580,000
Share-Based Payment Arrangement, Expense	$ 76,000	$ 109,000	$ 235,000	$ 312,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 84,000		$ 84,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			5 years