Gain on Sale of Idle Property, Plant and Equipment (Details) (USD $)	3 Months Ended		6 Months Ended
	Nov. 30, 2012	Nov. 30, 2011	Nov. 30, 2012	Nov. 30, 2011
Gain on Sale of Idle Property Plant and Equipment (Textual) [Abstract]
Gain on the sale of idle facilities	$ 1,411,000	$ 2,500,000	$ 1,411,000	$ 2,500,000
Recreational Vehicles [Member]
Gain on Sale of Idle Property Plant and Equipment (Textual) [Abstract]
Number of idle facilities sold	2		2
Hemet, California [Member] | Recreational Vehicles [Member]
Gain on Sale of Idle Property Plant and Equipment (Textual) [Abstract]
Gain on the sale of idle facilities	1,411,000
Ocala, Florida [Member] | Recreational Vehicles [Member]
Gain on Sale of Idle Property Plant and Equipment (Textual) [Abstract]
Gain on the sale of idle facilities		1,114,000
Ephrata, Pennsylvania [Member] | Recreational Vehicles [Member]
Gain on Sale of Idle Property Plant and Equipment (Textual) [Abstract]
Gain on the sale of idle facilities		$ 1,386,000