Receivables - Narrative (Details) - USD ($) $ in Thousands	6 Months Ended
	Feb. 28, 2018	Aug. 31, 2017	Feb. 28, 2017
Notes Receivable, Long-Term
Interest Income Accrual Term, Discontinued	90 days
CHS Capital long-term notes receivable additional available credit of counterparty	$ 348,600
Deferred purchase price receivable	$ 517,759	$ 548,602	$ 0
Maximum [Member]
Notes Receivable, Short-Term
CHS Capital notes receivable, current, term	12 months
CHS Capital Notes Receivable [Member]
Notes Receivable, Long-Term
CHS Capital long-term notes receivable, non-current, term	10 years
CHS Capital long-term notes receivable	$ 600	$ 17,000
Commercial Notes to Notes and Loans Receivable, Net, Percentage	3.00%	17.00%
Producer Notes to Notes and Loans Receivable, Net, Percentage	97.00%	83.00%