Note 3 - Acquired Identifiable Intangible Assets (Details) - Zenith Freight Lines [Member] $ in Thousands	9 Months Ended
Aug. 27, 2016 USD ($)
Customer Relationships [Member]
Useful Life In Years	15 years
Fair Value	$ 3,038
Technology-Based Intangible Assets [Member]
Useful Life In Years	7 years
Fair Value	$ 834
Trade Names [Member]
Fair Value	2,490
Fair Value	$ 6,362

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	us-gaap_FiniteLivedIntangibleAssetUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration