Note 4 - Net Sales - Accounts Receivables and Contract Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Accounts receivable - trade	$ 75,597	$ 64,017
Current contract assets	38,030	49,236
Current contract liabilities	$ 1,372	$ 437

Amount, after 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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