Note 5 - Accounts Receivable - Activity in Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Nov. 28, 2020	Nov. 30, 2019	Nov. 24, 2018
Balance, beginning of the year	$ 815	$ 754
Additions charged to expense	492	61	$ 339
Reductions to allowance, net	(96)	0
Balance, end of the year	$ 1,211	$ 815	$ 754