Note 7 - Receivables, Net - Schedule of Receivables (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Gross receivables	$ 544,262	$ 547,791
Less: allowance for credit losses	3,450	374
Total net receivables	540,812	547,417
Completed and in Progress [Member]
Billed	293,376	299,633
Unbilled	148,159	149,696
Gross receivables	441,535	449,329
Material Sales [Member]
Gross receivables	49,991	42,936
Other Business Products and Services [Member]
Gross receivables	$ 52,736	$ 55,526

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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Amount of allowance for credit loss on accounts receivable, classified as current.

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