Note 10 - Financial Information about Geographic Areas (Details Textual) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Revenue from Contract with Customer, Including Assessed Tax	$ 17,373,000	$ 17,806,000	$ 35,034,000	$ 40,967,000
CANADA
Revenue from Contract with Customer, Including Assessed Tax	$ 542,000	$ 103,000	$ 1,016,000	$ 2,258,000