Note 12 - Segment Information (Detail) - Segment Reporting Information (USD $)	3 Months Ended
	Feb. 28, 2013	Feb. 29, 2012	Nov. 30, 2012
Revenue from external customers	$ 8,415,000	$ 6,312,000
Income (loss) from operations	712,748	362,253
Income (loss) before tax	1,261,427	289,077
Total Assets	32,731,982	28,162,000	31,228,676
Capital expenditures	144,000	106,000
Depreciation & Amortization	199,000	206,000
Agricultural Products [Member]
Revenue from external customers	7,004,000	3,988,000
Income (loss) from operations	561,000	136,000
Income (loss) before tax	1,176,000	137,000
Total Assets	26,697,000	20,633,000
Capital expenditures	139,000	77,000
Depreciation & Amortization	151,000	124,000
Pressurized Vessels [Member]
Revenue from external customers	394,000	330,000
Income (loss) from operations	(123,000)	(88,000)
Income (loss) before tax	(176,000)	(144,000)
Total Assets	2,707,000	2,773,000
Capital expenditures	4,000	14,000
Depreciation & Amortization	26,000	29,000
Modular Buildings [Member]
Revenue from external customers	1,017,000	1,994,000
Income (loss) from operations	275,000	314,000
Income (loss) before tax	261,000	296,000
Total Assets	3,328,000	4,756,000
Capital expenditures	1,000	15,000
Depreciation & Amortization	$ 22,000	$ 53,000