Industry Segment Information (Details) (USD $)	3 Months Ended		6 Months Ended
	Nov. 30, 2012	Nov. 30, 2011	Nov. 30, 2012	Nov. 30, 2011
Net sales
Net Sales In Percentage	100.00%	100.00%	100.00%	100.00%
Net sales	$ 41,836,000	$ 45,296,000	$ 91,756,000	$ 95,580,000
Operating Loss
Gain on sale of idle property, plant and equipment	1,411,000	2,500,000	1,411,000	2,500,000
Total operating loss	(1,734,000)	(3,426,000)	(5,205,000)	(10,278,000)
Interest income	9,000	4,000	12,000	11,000
Loss before income taxes	(1,725,000)	(3,422,000)	(5,193,000)	(10,267,000)
Housing [Member]
Net sales
Net Sales In Percentage	68.00%	71.00%	65.00%	64.00%
Net sales	28,545,000	32,160,000	59,457,000	61,303,000
Operating Loss
Total operating loss	(1,733,000)	(3,400,000)	(3,370,000)	(7,806,000)
Housing [Member] | Modular Housing [Member]
Net sales
Net Sales In Percentage	17.00%	16.00%	17.00%	13.00%
Net sales	7,257,000	7,043,000	15,036,000	12,510,000
Housing [Member] | Domestic [Member] | Manufactured Housing [Member]
Net sales
Net Sales In Percentage	51.00%	55.00%	48.00%	51.00%
Net sales	21,288,000	25,117,000	44,421,000	48,793,000
Housing [Member] | Domestic [Member] | Modular Housing [Member]
Net sales
Net Sales In Percentage	14.00%	10.00%	13.00%	9.00%
Net sales	5,755,000	4,541,000	11,792,000	8,754,000
Housing [Member] | Canadian [Member] | Modular Housing [Member]
Net sales
Net Sales In Percentage	3.00%	6.00%	4.00%	4.00%
Net sales	1,502,000	2,502,000	3,244,000	3,756,000
Recreational Vehicles [Member]
Net sales
Net Sales In Percentage	32.00%	29.00%	35.00%	36.00%
Net sales	13,291,000	13,136,000	32,299,000	34,277,000
Operating Loss
Total operating loss	(929,000)	(1,865,000)	(2,253,000)	(3,740,000)
Recreational Vehicles [Member] | Domestic [Member]
Net sales
Net Sales In Percentage	25.00%	25.00%	29.00%	29.00%
Net sales	10,460,000	11,437,000	26,393,000	27,599,000
Recreational Vehicles [Member] | Canadian [Member]
Net sales
Net Sales In Percentage	7.00%	4.00%	6.00%	7.00%
Net sales	2,831,000	1,699,000	5,906,000	6,678,000
General Corporate Expense [Member]
Operating Loss
Total operating loss	$ (483,000)	$ (661,000)	$ (993,000)	$ (1,232,000)