Note 8 - Receivables, Net - Schedule of Receivables (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020
Gross receivables	$ 649,203	$ 544,262	$ 599,341
Less: allowance for credit losses	2,263	3,450	2,419
Total net receivables	646,940	540,812	596,922
Completed and in Progress [Member]
Billed	259,319	293,376	311,550
Unbilled	217,025	148,159	163,815
Gross receivables	476,344	441,535	475,365
Material Sales [Member]
Gross receivables	66,929	49,991	58,514
Other Business Products and Services [Member]
Gross receivables	$ 105,930	$ 52,736	$ 65,462

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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