Note 3 - Revenue Recognition 1 (Details Textual) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Contract with Customer, Liability, Revenue Recognized	$ 0.2	$ 0.2
Accounts Receivable, Allowance for Credit Loss, Ending Balance	$ 1.8		$ 1.7