Note 9 - Accounts Receivable Securitization (Details Textual) - Line of Credit [Member] - Accounts Receivable Securitization Facility [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Line of Credit Facility, Maximum Borrowing Capacity	$ 100,000
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.60%
Accounts Receivable Eligible for Securitization	$ 29,858		$ 21,649
Line of Credit Facility, Fair Value of Amount Outstanding	0		0
Letters of Credit Outstanding, Amount	29,681		21,806
Line of Credit Facility, Remaining Borrowing Capacity	177		$ 0
Debt Instrument, Collateral Amount	157
Payments of Financing Costs, Total	275	$ 261
Restricted Cash, Current [Member]
Debt Instrument, Collateral Amount	$ 157
Minimum [Member]
Line of Credit Facility, Commitment Fee Percentage	2.00%
Maximum [Member]
Line of Credit Facility, Commitment Fee Percentage	2.50%