Note 8 - Property, Plant and Equipment (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Interest Paid, Capitalized, Investing Activities	$ 2,001	$ 1,140
Amortization of Leased Asset	676	846
Operating Leases, Rent Expense, Net, Total	8,173	7,763
Construction in Progress [Member]
Interest Paid, Capitalized, Investing Activities	$ 2,001	$ 1,140
Capitalization Rates	7.29%	6.71%