Equities Changes in Equity (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Mar. 31, 2016	Jun. 30, 2014	Feb. 29, 2016	Feb. 28, 2015	Feb. 29, 2016	Feb. 28, 2015	Aug. 31, 2015	Jan. 30, 2015	Sep. 30, 2014
Schedule of Capitalization, Equity [Line Items]
Preferred stock, Value available for issuance					$ 990,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Reversal of prior year patronage and redemption estimates					260,620
Patronage Refunds					251,535
Redemptions of equities					(10,443)
Equities issued, net					16,565
Dividends, Preferred Stock					(80,999)
Other, net					(4,556)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest			$ (30,182)	$ 92,897	235,992	$ 471,228
Net income (loss) attributable to CHS Inc.			(30,979)	92,814	235,496	471,517
Net income (loss) attributable to noncontrolling interests			797	83	496	(289)
Other Comprehensive Income (Loss), Net of Tax			(10,947)	$ (4,551)	(14,500)	(5,638)
Patronage Refunds, Estimated					(53,446)
Equity redemptions, estimate					(64,680)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			7,702,429		7,702,429		$ 7,669,411
Capital equity certificates [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Reversal of prior year patronage and redemption estimates					(364,824)
Patronage Refunds					(375,330)
Redemptions of equities					(10,136)
Equities issued, net					16,565
Other, net					665
Equity redemptions, estimate					(64,680)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			3,746,817		3,746,817		3,793,897
Noncontrolling Interest [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other, net					3,286
Net income (loss) attributable to noncontrolling interests					496
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			15,308		15,308		11,526
Nonpatronage Equity Certificates [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Reversal of prior year patronage and redemption estimates					0
Patronage Refunds					0
Redemptions of equities					(50)
Other, net					(20)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			22,987		22,987		23,057
Non-qualified Equity Certificates [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Reversal of prior year patronage and redemption estimates					0
Patronage Refunds					0
Redemptions of equities					(257)
Other, net					(313)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			282,358		282,358		282,928
Preferred Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Reversal of prior year patronage and redemption estimates					0
Patronage Refunds					0
Redemptions of equities					0
Other, net					(73)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			2,167,467		2,167,467		2,167,540
Accumulated Other Comprehensive Income (Loss) [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Reversal of prior year patronage and redemption estimates					0
Patronage Refunds					0
Redemptions of equities					0
Other Comprehensive Income (Loss), Net of Tax					(14,500)	$ (5,638)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			(228,707)		(228,707)		(214,207)
Capital Reserves [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Reversal of prior year patronage and redemption estimates					625,444
Patronage Refunds					626,865
Redemptions of equities					0
Dividends, Preferred Stock					(80,999)
Other, net					(8,101)
Net income (loss) attributable to CHS Inc.					235,496
Patronage Refunds, Estimated					(53,446)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			$ 1,696,199		$ 1,696,199		1,604,670
Class B, Series 4 Preferred Stock [Member]
Schedule of Capitalization, Equity [Line Items]
Preferred Stock, Redemption Amount								$ 517,500
Proceeds from Issuance of Preferred Stock, net of Issuance Costs							501,000
Preferred Stock, Dividend Rate, Percentage					7.50%
Preferred Stock, Shares Issued								20,700,000
Class B Preferred Stock [Member]
Schedule of Capitalization, Equity [Line Items]
Value of Preferred Stock available to be sold under Shelf Registration		$ 2,000,000
Class B, Series 3 Preferred Stock [Member]
Schedule of Capitalization, Equity [Line Items]
Preferred Stock, Redemption Amount									$ 492,500
Proceeds from Issuance of Preferred Stock, net of Issuance Costs							$ 476,700
Preferred Stock, Dividend Rate, Percentage					6.75%
Preferred Stock, Shares Issued									19,700,000
Subsequent Event [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Redeemed or Called During Period, Price per Share	$ 28.50
Subsequent Event [Member] | Capital equity certificates [Member]
Schedule of Capitalization, Equity [Line Items]
Stock Redeemed or Called During Period, Value	$ 76,800
Subsequent Event [Member] | Class B, Series 4 Preferred Stock [Member]
Schedule of Capitalization, Equity [Line Items]
Preferred Stock, Redemption Amount	$ 67,300
Subsequent Event [Member] | Class B, Series 1 Preferred Stock [Member]
Schedule of Capitalization, Equity [Line Items]
Preferred Stock, Dividend Rate, Percentage	7.785%
Preferred Stock, Shares Issued	2,693,195
London Interbank Offered Rate (LIBOR) [Member] | Class B, Series 3 Preferred Stock [Member]
Schedule of Capitalization, Equity [Line Items]
Preferred Stock, Basis Spread on Dividend Rate Percentage					4.155%
Maximum [Member] | London Interbank Offered Rate (LIBOR) [Member] | Class B, Series 3 Preferred Stock [Member]
Schedule of Capitalization, Equity [Line Items]
Preferred Stock, Basis Spread on Dividend Rate Percentage					8.00%