Note 6 - Accounting for Share-based Compensation - Deferred Compensation Units (Details)	9 Months Ended
	Aug. 31, 2019 shares
Units outstanding (in shares)	509,522
Participant contributions (in shares)	25,395
Company match contributions (in shares)	24,044
Payouts (in shares)	(4,651)
Units outstanding (in shares)	554,310
Non Employee Directors [Member]
Units outstanding (in shares)	479,787
Participant contributions (in shares)	16,900
Company match contributions (in shares)	23,194
Payouts (in shares)	0
Units outstanding (in shares)	519,881
Employees [Member]
Units outstanding (in shares)	29,735
Participant contributions (in shares)	8,495
Company match contributions (in shares)	850
Payouts (in shares)	(4,651)
Units outstanding (in shares)	34,429