Note 2 - New Accounting Pronouncements - Contract Assets (Liabilities) (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2018	Dec. 31, 2017
Contract assets (*)	[1]	$ 41,134	$ 40,945
Contract liabilities (*)	[1]	(10,458)	(20,241)
Contract assets, net		30,676	$ 20,704
Recognition of contract liabilities as revenue as a result of performance obligations satisfied, liabilities		8,353
Cash received in advance for which revenues have not yet recognized, liabilities		(4,451)
Reduction of contract assets as a result of rights to consideration becoming unconditional, assets		(22,144)
Contract assets recognized, net of recognized receivables, assets		28,214
Net change in contract assets and contract liabilities, assets		6,070
Net change in contract assets and contract liabilities, liabilities		$ 3,902

[1] Contract assets and contract liabilities are presented as Costs and estimated earnings in excess of billings on uncompleted contracts and Billings in excess of costs and estimated earnings on uncompleted contracts, respectively, on the consolidated balance sheet.