Receivables - Narrative (Details) (USD $) In Millions, unless otherwise specified	Aug. 31, 2012	Aug. 31, 2011
Notes Receivable, Long-Term
CHS Capital long-term notes receivable	$ 164.8	$ 151.1
Percentage of commercial notes to CHS Capital long-term notes receivable	74.00%	84.00%
Percentage of producer notes to CHS Capital long-term notes receivable	26.00%	16.00%
Interest income accrual, discontinue, term	90 days
Minimum
Notes Receivable, Short-Term
CHS Capital short-term notes receivable, term	12 months
Maximum
Notes Receivable, Short-Term
CHS Capital short-term notes receivable, term	14 months
Notes and Loans Receivable, Net, Noncurrent, Term	10 years