Note 17 - Segment Information (Detail) - Financial information with respect to the reportable segments (USD $)	12 Months Ended
	Nov. 30, 2012	Nov. 30, 2011
Revenue from external customers	$ 36,457,000	$ 27,620,000
Gross Profit	10,032,263	7,007,010
Operating Expense	5,704,438	5,077,246
Income from operations	4,328,000	1,930,000
Income before tax	3,988,027	1,580,934
Total Assets	31,229,000	25,855,000
Capital expenditures	800,000	1,092,000
Depreciation & Amortization	853,000	780,000
Agricultural Products [Member]
Revenue from external customers	24,720,000	22,614,000
Gross Profit	6,945,000	6,481,000
Operating Expense	4,572,000	4,053,000
Income from operations	2,373,000	2,428,000
Income before tax	2,326,000	2,378,000
Total Assets	24,155,000	19,965,000
Capital expenditures	753,000	569,000
Depreciation & Amortization	531,000	469,000
Pressurized Vessels [Member]
Revenue from external customers	2,092,000	1,797,000
Gross Profit	146,000	(112,000)
Operating Expense	273,000	336,000
Income from operations	(127,000)	(448,000)
Income before tax	(355,000)	(674,000)
Total Assets	2,846,000	2,768,000
Capital expenditures	14,000	100,000
Depreciation & Amortization	113,000	105,000
Modular Buildings [Member]
Revenue from external customers	9,645,000	3,209,000
Gross Profit	2,941,000	638,000
Operating Expense	859,000	688,000
Income from operations	2,082,000	(50,000)
Income before tax	2,017,000	(123,000)
Total Assets	4,228,000	3,122,000
Capital expenditures	33,000	423,000
Depreciation & Amortization	$ 209,000	$ 206,000