Note 13 - Employee Stock Option and Retirement Plans (Details) - Summary of Share-Based Awards Available For Grant - shares		3 Months Ended						6 Months Ended	9 Months Ended
		May. 31, 2015		Feb. 28, 2015		Nov. 30, 2014		Feb. 28, 2015	May. 31, 2015	May. 31, 2014
2004 Stock Option and Award Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Balance		2,554,000		2,768,000		3,222,000		3,222,000	3,222,000
Share-based awards canceled/forfeited	[1]	39,000		44,000		35,000
Balance		2,530,000		2,554,000		2,768,000		2,554,000	2,530,000
Non-Employee Directors' Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Balance		88,000		102,000		102,000		102,000	102,000
Share-based awards canceled/forfeited	[1]	0		0		0
Balance		88,000		88,000		102,000		88,000	88,000
Non-performance Based [Member] | 2004 Stock Option and Award Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted – options		(61,000)		(25,000)		(463,000)
Non-performance Based [Member] | Non-Employee Directors' Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted – options		0		(14,000)		0
Performance Shares [Member] | 2004 Stock Option and Award Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted – options				(138,000)		0
Performance Shares [Member] | Non-Employee Directors' Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted – options				0		0
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards granted		(38,000)		(1,000)		(10,000)			(49,158)	(204,124)
Restricted Stock [Member] | 2004 Stock Option and Award Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards granted		(2,000)	[2]	(95,000)	[2]	(26,000)	[2]		(49,158)
Restricted Stock [Member] | Non-Employee Directors' Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards granted	[2]	0		0		0

[1] Under the Company's option plan, for each restricted stock award canceled/forfeited, an equivalent of 2.5 shares is added back to the available share-based awardsbalance.

[2] Each restricted stock award granted is equivalent to 2.5 shares granted under the Company's option plan.