Note 10 - Stock-based Compensation Expense - Stock Compensation Expense (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share-based Payment Arrangement, Expense	$ 420,000
Awards issued and vested (in shares)	258,000
Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Expense	$ 2,000	$ 17,000
Awards issued and vested (in shares)	5,000
Restricted Stock Units (RSUs) [Member]
Awards issued and vested (in shares)	168,000	134,000
Restricted Stock Units (RSUs) [Member] | Chief Executive Officer [Member]
Share-based Payment Arrangement, Expense	$ 331,000
Awards issued and vested (in shares)	130,000
Restricted Stock Units (RSUs) [Member] | Non Employee Directors [Member]
Share-based Payment Arrangement, Expense	$ 75,000
Awards issued and vested (in shares)	121,000
Restricted Stock Units (RSUs) [Member] | Non Employee Directors and Corporate Secretary [Member]
Share-based Payment Arrangement, Expense	$ 12,000
Awards issued and vested (in shares)	2,000