Note 4 - Accounts Receivable, Transit Accounts Receivable and Transit Accounts Payable (Details Textual) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Accounts Receivable, after Allowance for Credit Loss, Current, Total	$ 59,760	$ 52,335
Loss Contingency, Receivable, Ending Balance	14,100	8,900
Loss Contingency, Estimate of Possible Loss	10,300
Collectibility of Receivables [Member]
Loss Contingency, Estimate of Possible Loss	10,300
Transit Accounts Payable [Member]
Accounts Payable, Current, Total	4,600	2,500
Transit Accounts Receivable [Member]
Accounts Receivable, before Allowance for Credit Loss, Current	4,900	2,600
Accounts Receivable, after Allowance for Credit Loss, Current, Total	300	$ 100
Transit Accounts Payable [Member]
Accounts Payable, Current, Total	$ 4,600