Note 9 - Equity Investments - Summarized Financial Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current assets	$ 23,325	$ 37,131
Non-current assets	29,297	43,718
Total Assets	52,622	80,849
Current liabilities	54,733	66,726
Non-current liabilities	83,085	89,723
Total Liabilities	137,818	156,449
Net Liabilities	(85,196)	(75,600)
Total operating revenue	158,414	243,311	$ 233,905
Operating expenses	151,523	247,384	240,157
Operating income (loss)	6,891	(4,073)	(6,252)
Net loss	$ (3,679)	$ (12,023)	$ (16,917)