Note 2 - Revenue Recognition (Details Textual) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Revenue from Contract with Customer, Excluding Assessed Tax	$ 6,525,000	$ 10,394,000	$ 14,666,000	$ 20,126,000
Contract with Customer, Asset, Credit Loss Expense (Reversal)	0	0	0	0
Capitalized Contract Cost, Amortization	0	4,000	11,250	9,000
Capitalized Contract Cost, Impairment Loss	0	0	$ 0	0
Minimum [Member]
Customer Payment Terms (Day)			30 days
Maximum [Member]
Customer Payment Terms (Day)			60 days
Transferred at Point in Time [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	6,400,000	9,900,000	$ 14,400,000	19,100,000
Transferred over Time [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 100,000	$ 500,000	$ 300,000	$ 1,000,000.0