Note 13 - Segment Information (Details Textual) $ in Thousands	3 Months Ended	6 Months Ended
May 26, 2018 USD ($)	May 27, 2017 USD ($)	May 26, 2018 USD ($)	May 27, 2017 USD ($)
Number of Reportable Segments			3
SGA Expenses Excluding New Store Pre-opening Costs	$ 65,456	$ 61,075	$ 129,707	$ 119,599
Zenith Freight Lines [Member]
SGA Expenses Excluding New Store Pre-opening Costs	$ 24,640	$ 23,828	$ 49,559	$ 46,388

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

No definition available.

Name:	us-gaap_NumberOfReportableSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration