Notes Payable and Long-Term Debt - Footnote Narrative (Details) (USD $)											6 Months Ended
	Feb. 28, 2014	Aug. 31, 2013	Feb. 28, 2013	Feb. 28, 2014 CHS Capital notes payable	Aug. 31, 2013 CHS Capital notes payable	Feb. 28, 2013 CHS Capital notes payable	Feb. 28, 2014 Notes payable	Aug. 31, 2013 Notes payable	Feb. 28, 2013 Notes payable	Feb. 28, 2014 Five-Year Revolving Facilities [Member] Line of Credit [Member] Revolving credit facility	Feb. 28, 2014 Reclassification out of Accumulated Other Comprehensive Income [Member] Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Debt Instrument [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax											$ 13,500,000
Notes payable	1,074,280,000	889,312,000	858,496,000	426,178,000	367,448,000	438,960,000	648,102,000	521,864,000	419,536,000
Line of Credit Facility, Current Borrowing Capacity										$ 2,500,000,000