Note 8 - Receivables, Net - Schedule of Receivables (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020
Gross receivables	$ 686,506	$ 544,262	$ 665,213
Less: allowance for credit losses	1,684	3,450	3,265
Total net receivables	684,822	540,812	661,948
Completed and in Progress [Member]
Billed	278,313	293,376	355,293
Unbilled	217,534	148,159	167,311
Gross receivables	495,847	441,535	522,604
Material Sales [Member]
Gross receivables	80,357	49,991	70,918
Other Business Products and Services [Member]
Gross receivables	$ 110,302	$ 52,736	$ 71,691

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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