Note 9 - Receivables, Net - Schedule of Receivables (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Gross receivables	$ 599,341	$ 547,791	$ 565,184
Less: allowance for credit losses	2,419	374	641
Total net receivables	596,922	547,417	564,543
Completed and in Progress [Member]
Billed	311,550	299,633	313,185
Unbilled	163,815	149,696	163,950
Gross receivables	475,365	449,329	477,135
Material Sales [Member]
Gross receivables	58,514	42,936	61,204
Other Business Products and Services [Member]
Gross receivables	$ 65,462	$ 55,526	$ 26,845

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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