Note 8 - Accounting for Share-based Compensation - Deferred Compensation Units (Details)	9 Months Ended
	Sep. 02, 2017 shares
Units outstanding (in shares)	465,435
Participant contributions (in shares)	28,917
Company match contributions (in shares)	2,891
Payouts (in shares)	(26,695)
Units outstanding (in shares)	470,548
Non Employee Directors [Member]
Units outstanding (in shares)	424,319
Participant contributions (in shares)	23,864
Company match contributions (in shares)	2,386
Payouts (in shares)	(14,143)
Units outstanding (in shares)	436,426
Employees [Member]
Units outstanding (in shares)	41,116
Participant contributions (in shares)	5,053
Company match contributions (in shares)	505
Payouts (in shares)	(12,552)
Units outstanding (in shares)	34,122