Note 4 - Accounts Receivable, Transit Accounts Receivable and Transit Accounts Payable - Accounts Receivable (Details) - USD ($) $ in Thousands	Apr. 03, 2021	Jan. 02, 2021
Allowance for sales discounts and doubtful accounts	$ (1,418)	$ (1,750)
Accounts receivable, net	45,282	36,007
Billed Revenues [Member]
Accounts receivable, current	31,529	25,926
Unbilled Revenues [Member]
Accounts receivable, current	11,636	8,219
Work In Progress [Member]
Accounts receivable, current	$ 3,535	$ 3,612

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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