Note 4 - Accounts Receivable, Transit Accounts Receivable and Transit Accounts Payable - Accounts Receivable (Details) - USD ($) $ in Thousands	Sep. 29, 2018	Dec. 30, 2017
Allowance for sales discounts and doubtful accounts	$ (1,278)	$ (967)
Accounts receivable, net	46,663	46,080
Billed Revenues [Member]
Accounts receivable, current	30,106	31,448
Unbilled Revenues [Member]
Accounts receivable, current	12,131	10,573
Work In Progress [Member]
Accounts receivable, current	$ 5,704	$ 5,026

Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

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+ References

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- Definition

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