Accrued Expenses (Details) - USD ($) $ in Thousands	Aug. 31, 2017	Aug. 31, 2016
Accrued Liabilities, Current [Abstract]
Deferred income	$ 1,017,144	$ 893,148
Accrued compensation and employee benefits	534,143	449,183
Other accrued expenses	616,185	586,720
Accrued expenses	$ 2,167,472	$ 1,929,051