Note 13 - Segment Information - Segment Reporting Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Aug. 31, 2015	Aug. 31, 2014	Aug. 31, 2015	Aug. 31, 2014
Operating Segments [Member] | Agricultural Products [Member]
Revenue from external customers	$ 4,911,000	$ 9,362,000	$ 16,592,000	$ 21,366,000
Income (loss) from operations	(861,000)	1,034,000	158,000	1,430,000
Income (loss) before tax	(1,019,000)	991,000	(83,000)	1,292,000
Total Assets	24,540,000	26,426,000	24,540,000	26,426,000
Capital expenditures	71,000	39,000	204,000	629,000
Depreciation & Amortization	159,000	147,000	426,000	356,000
Operating Segments [Member] | Pressurized Vessels [Member]
Revenue from external customers	372,000	606,000	1,374,000	1,504,000
Income (loss) from operations	(105,000)	(59,000)	(171,000)	(168,000)
Income (loss) before tax	(113,000)	(64,000)	(191,000)	(190,000)
Total Assets	2,511,000	$ 2,489,000	2,511,000	2,489,000
Capital expenditures	8,000		10,000	11,000
Depreciation & Amortization	27,000	$ 27,000	80,000	81,000
Operating Segments [Member] | Modular Buildings [Member]
Revenue from external customers	1,103,000	820,000	2,162,000	1,818,000
Income (loss) from operations	45,000	$ 7,000	(119,000)	(233,000)
Income (loss) before tax	38,000		(139,000)	(249,000)
Total Assets	2,691,000	$ 2,842,000	2,691,000	$ 2,842,000
Capital expenditures	6,000		4,000
Depreciation & Amortization	31,000	$ 36,000	98,000	$ 110,000
Operating Segments [Member] | Tools [Member]
Revenue from external customers	500,000	797,000	1,851,000	2,603,000
Income (loss) from operations	(83,000)	(74,000)	(128,000)	28,000
Income (loss) before tax	(91,000)	(82,000)	(173,000)	(18,000)
Total Assets	2,963,000	3,334,000	2,963,000	3,334,000
Capital expenditures	6,000	1,000	11,000	11,000
Depreciation & Amortization	30,000	29,000	89,000	86,000
Operating Segments [Member]
Revenue from external customers	6,886,000	11,585,000	21,979,000	27,291,000
Income (loss) from operations	(1,004,000)	908,000	(260,000)	1,057,000
Income (loss) before tax	(1,185,000)	845,000	(586,000)	835,000
Total Assets	32,705,000	35,091,000	32,705,000	35,091,000
Capital expenditures	91,000	40,000	229,000	651,000
Depreciation & Amortization	247,000	239,000	692,000	633,000
Revenue from external customers	6,886,077	11,584,707	21,979,317	27,291,037
Income (loss) from operations	(1,003,584)	907,772	(260,284)	1,056,728
Income (loss) before tax	(1,185,100)	$ 844,525	(586,264)	835,425
Total Assets	$ 32,704,696		32,704,696
Capital expenditures			228,624	651,251
Depreciation & Amortization			$ 692,680	$ 633,123