Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Nov. 30, 2017	Nov. 30, 2016
Net income (loss)	$ 179,619	$ 208,942
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract]
Postretirement benefit plan activity, net of tax expense (benefit)	4,196	3,239
Unrealized net gain (loss) on available for sale investments, net of tax expense (benefit)	3,640	777
Cash flow hedges, net of tax expense (benefit)	(4)	654
Foreign currency translation adjustment, net of tax expense (benefit)	(2,607)	(19,164)
Other comprehensive income (loss), net of tax	5,225	(14,494)
Comprehensive income (loss)	184,844	194,448
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	(464)	(208)
Net income (loss) attributable to noncontrolling interests	(464)	(208)
Comprehensive Income (Loss) Attributable to CHS	$ 185,308	$ 194,656