Note 13 - Segment Information (Details Textual) $ in Thousands	3 Months Ended	9 Months Ended
Aug. 25, 2018 USD ($)	Aug. 26, 2017 USD ($)	Aug. 25, 2018 USD ($)	Aug. 26, 2017 USD ($)
Number of Reportable Segments			3
SGA Expenses Excluding New Store Pre-opening Costs	$ 63,279	$ 61,373	$ 192,986	$ 180,972
Zenith Freight Lines [Member]
SGA Expenses Excluding New Store Pre-opening Costs	$ 23,396	$ 23,761	$ 72,955	$ 70,149

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