Note 16 - Leases - Supplemental Balance Sheet Information (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Operating Lease, Right-of-Use Asset	$ 14,217	$ 18,504
Operating lease liability, current	6,591	7,377
Operating lease liability, long-term	8,064	11,751
Total operating lease liabilities	14,655
Property, plant and equipment, gross	146,749	168,377
Accumulated depreciation	(112,248)	(126,434)
Property, plant and equipment, net	34,501	$ 41,943
Other current liabilities	198
Other long-term liabilities	790
Total finance lease liabilities	988
Assets under Finance Lease [Member]
Property, plant and equipment, gross	966
Accumulated depreciation	(391)
Property, plant and equipment, net	$ 575