Inventories (Details) (USD $)	Feb. 28, 2013	Aug. 31, 2012	Feb. 29, 2012
Inventories
Sugar, Agri-Products, and Sugarbeet Seed	$ 453,811,000	$ 193,352,000	$ 463,796,000
Unprocessed Sugarbeets	208,797,000	11,575,000	148,531,000
Operating Supplies and Maintenance Parts	61,168,000	67,759,000	63,443,000
Total Inventories	723,776,000	272,686,000	675,770,000
Reserve for inventory obsolescence	$ 17,800,000	$ 16,900,000	$ 15,400,000