Note 5 - Net Sales - Accounts Receivables and Contract Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accounts receivable	$ 103,066	$ 101,902
Current contract assets	40,662	39,231
Current contract liabilities	$ 6,397	$ 5,074

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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