Note 8 - Receivables, Net - Schedule of Receivables (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018
Gross receivables	$ 701,295	$ 473,757	$ 618,159
Less: allowance for doubtful accounts	908	511	89
Total net receivables	700,387	473,246	618,070
Completed and in Progress [Member]
Billed	417,373	285,521	351,802
Unbilled	182,762	98,755	147,950
Gross receivables	600,135	384,276	499,752
Material Sales [Member]
Gross receivables	72,486	45,286	73,282
Other Business Products and Services [Member]
Gross receivables	$ 28,674	$ 44,195	$ 45,125

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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