Note 5 - Net Sales - Accounts Receivable and Contract Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Accounts receivable	$ 101,591	$ 101,902
Current contract assets	41,151	39,231
Current contract liabilities	$ 5,559	$ 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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