Receivables - Narrative (Details) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
May 31, 2017 USD ($) a	May 31, 2017 USD ($) a	Aug. 31, 2016 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Doubtful Accounts Receivable, Period Increase (Decrease)	$ 98.7
Valuation Allowances and Reserves, Additions for Charges to Other Accounts	$ 130.7
Notes Receivable, Long-Term
Area of Land \| a	14,000	14,000
Land credited against debt, Value	$ 139.0	$ 139.0
Interest Income Accrual Term, Discontinued		90 days
CHS Capital long-term notes receivable additional available credit of counterparty	966.2	$ 966.2
Minimum [Member]
Notes Receivable, Short-Term
CHS Capital notes receivable, current, term		12 months
Maximum [Member]
Notes Receivable, Short-Term
CHS Capital notes receivable, current, term		14 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	$ 252.4	$ 252.4	$ 322.4
Commercial Notes to Notes and Loans Receivable, Net, Percentage	52.00%	52.00%	26.00%
Producer Notes to Notes and Loans Receivable, Net, Percentage	48.00%	48.00%	74.00%
Financing Receivable, Percent Past Due		5.00%	2.50%
CHS Capital loan loss reserves	$ 17.2	$ 17.2	$ 45.8
Customer Concentration Risk [Member] \| CHS Capital Notes Receivable [Member]
Notes Receivable, Long-Term
Concentration Risk, Percentage			20.00%

Commercial Notes to Notes and Loans Receivable, Net, Percentage

No definition available.

Name:	chscp_CommercialNotestoNotesandLoansReceivableNetPercentage
Namespace Prefix:	chscp_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Interest Income Accrual Term, Discontinued

+ References

No definition available.

+ Details

Name:	chscp_InterestIncomeAccrualTermDiscontinued
Namespace Prefix:	chscp_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Land credited against note receivable, Value

+ References

No definition available.

+ Details

Name:	chscp_LandcreditedagainstnotereceivableValue
Namespace Prefix:	chscp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Land received as collateral, area

+ References

No definition available.

+ Details

Name:	chscp_Landreceivedascollateralarea
Namespace Prefix:	chscp_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

Notes and Loans Receivable, Current, Term

+ References

No definition available.

+ Details

Name:	chscp_NotesAndLoansReceivableCurrentTerm
Namespace Prefix:	chscp_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Notes and Loans Receivables, Net, Noncurrent, Remaining Borrowing Capacity of Counterparty

+ References

No definition available.

+ Details

Name:	chscp_NotesAndLoansReceivablesNetNoncurrentRemainingBorrowingCapacityOfCounterparty
Namespace Prefix:	chscp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Notes and Loans Receivable, Net, Non-Current, Term

+ References

No definition available.

+ Details

Name:	chscp_NotesandLoansReceivableNonCurrentNetTerm
Namespace Prefix:	chscp_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Producer Notes to Notes and Loans Receivable, Net, Percentage

+ References

No definition available.

+ Details

Name:	chscp_ProducerNotestoNotesandLoansReceivableNetPercentage
Namespace Prefix:	chscp_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_AccountsNotesAndLoansReceivableNetCurrentAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of increase (decrease) in the allowance for doubtful accounts.

+ References

No definition available.

+ Details

Name:	us-gaap_AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611

+ Details

Name:	us-gaap_ConcentrationRiskPercentage1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percent of financing receivables past due.

+ References

No definition available.

+ Details

Name:	us-gaap_FinancingReceivablePercentPastDue
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

+ Details

Name:	us-gaap_LoansAndLeasesReceivableAllowance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_LongTermAccountsNotesAndLoansReceivableNetNoncurrentAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date more than one year from the balance sheet date, net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_NotesAndLoansReceivableNetNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from charges to accounts other than costs and expenses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

+ Details

Name:	us-gaap_ValuationAllowancesAndReservesChargedToOtherAccounts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=chscp_CHSCapitalNotesReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CustomerConcentrationRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: