Note 2 - New Accounting Pronouncements - Contract Assets (Liabilities) (Details) - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2018	Dec. 31, 2017
Contract assets (*)	[1]	$ 46,573	$ 40,945
Contract liabilities (*)	[1]	(16,136)	(20,241)
Contract assets, net		30,437	$ 20,704
Recognition of contract liabilities as revenue as a result of performance obligations satisfied, liabilities		11,094
Cash received in advance for which revenues have not yet recognized, net expenditures made, liabilities		(12,901)
Reduction of contract assets as a result of rights to consideration becoming unconditional, assets		(59,634)
Contract assets recognized, net of recognized receivables, assets		71,174
Net change in contract assets and contract liabilities, assets		11,540
Net change in contract assets and contract liabilities, liabilities		$ (1,807)

[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.