Note 1 - Business and Significant Accounting Policies - Contract Assets (Liabilities) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017
Contract assets (*)	[1]	$ 42,130	$ 40,945
Contract liabilities (*)	[1]	(18,402)	(20,241)
Contract assets, net		23,728	$ 20,704
Recognition of contract liabilities as revenue as a result of performance obligations satisfied		33,349
Cash received in advance for which revenues have not yet recognized, net expenditures made		(38,162)
Reduction of contract assets as a result of rights to consideration becoming unconditional		(128,659)
Contract assets recognized, net of recognized receivables		136,496
Net change in contract assets and contract liabilities		7,837
Net change in contract assets and contract liabilities		$ (4,813)

[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.