Note 8 - Receivables, Net - Schedule of Receivables (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Gross receivables	$ 477,651	$ 544,262	$ 479,110
Less: allowance for credit losses	2,491	3,450	1,392
Total net receivables	475,160	540,812	477,718
Completed and in Progress [Member]
Billed	190,775	293,376	250,683
Unbilled	136,565	148,159	141,514
Gross receivables	327,340	441,535	392,197
Material Sales [Member]
Gross receivables	38,407	49,991	34,268
Other Business Products and Services [Member]
Gross receivables	$ 111,904	$ 52,736	$ 52,645

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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