Note 4 - Accounts Receivable, Transit Accounts Receivable and Transit Accounts Payable (Details Textual) - USD ($) $ in Thousands	Dec. 29, 2018	Dec. 30, 2017
Accounts Receivable, Net, Current, Total	$ 52,335	$ 46,080
Loss Contingency, Receivable, Ending Balance	8,900
Loss Contingency, Estimate of Possible Loss	10,600
Collectibility of Receivables [Member]
Loss Contingency, Estimate of Possible Loss	10,600
Transit Accounts Payable [Member]
Accounts Payable, Current, Total	2,500	4,700
Liabilities, Net		1,700
Transit Accounts Receivable [Member]
Accounts Receivable, Gross, Current	2,600	$ 3,000
Accounts Receivable, Net, Current, Total	$ 100