Note 12 - Segment Information (Details) - Segment Reporting Information (USD $)	3 Months Ended		6 Months Ended
	May 31, 2014	May 31, 2013	May 31, 2014	May 31, 2013	Nov. 30, 2013
Segment Reporting Information [Line Items]
Revenue from external customers	$ 9,468,996	$ 9,250,308	$ 15,706,331	$ 17,665,413
Income (loss) from operations	443,891	798,959	148,955	1,511,713
Income (loss) before tax	334,100	709,777	(9,102)	1,971,210
Total Assets	35,008,232		35,008,232		32,767,621
Capital expenditures			611,211	210,269
Depreciation & Amortization			441,230	370,084
Agricultural Products [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from external customers	7,562,000	7,716,000	12,004,000	14,720,000
Income (loss) from operations	600,000	568,000	396,000	1,129,000
Income (loss) before tax	541,000	517,000	301,000	1,693,000
Total Assets	26,147,000	25,531,000	26,147,000	25,531,000
Capital expenditures	162,000	58,000	574,000	197,000
Depreciation & Amortization	136,000	96,000	256,000	247,000
Pressurized Vessels [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from external customers	475,000	642,000	898,000	1,036,000
Income (loss) from operations	(78,000)	(12,000)	(109,000)	(135,000)
Income (loss) before tax	(85,000)	(38,000)	(125,000)	(214,000)
Total Assets	2,715,000	2,891,000	2,715,000	2,891,000
Capital expenditures	16,000	5,000	27,000	9,000
Depreciation & Amortization	27,000	26,000	54,000	52,000
Modular Buildings [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from external customers	537,000	892,000	998,000	1,909,000
Income (loss) from operations	(114,000)	243,000	(240,000)	518,000
Income (loss) before tax	(120,000)	231,000	(249,000)	492,000
Total Assets	2,708,000	3,024,000	2,708,000	3,024,000
Capital expenditures	0	3,000	0	4,000
Depreciation & Amortization	37,000	49,000	74,000	71,000
Tools [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from external customers	895,000	0	1,806,000	0
Income (loss) from operations	36,000	0	102,000	0
Income (loss) before tax	(2,000)	0	64,000	0
Total Assets	3,438,000	0	3,438,000	0
Capital expenditures	1,000	0	10,000	0
Depreciation & Amortization	28,000	0	57,000	0
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from external customers	9,469,000	9,250,000	15,706,000	17,665,000
Income (loss) from operations	444,000	799,000	149,000	1,512,000
Income (loss) before tax	334,000	710,000	(9,000)	1,971,000
Total Assets	35,008,000	31,446,000	35,008,000	31,446,000
Capital expenditures	179,000	66,000	611,000	210,000
Depreciation & Amortization	$ 228,000	$ 171,000	$ 441,000	$ 370,000