Goodwill and Other Intangible Assets, Schedule of Finite-Lived Intangible Assets by Major Class (Details) - USD ($) $ in Millions	Aug. 31, 2016	Aug. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Amortizable Intangible Assets	$ 4,044	$ 4,387
Accumulated amortization	1,439	1,090
Total amortizable intangible assets, net	2,605	3,297
Total Indefinite-Lived intangible assets	7,697	9,054
Total intangible assets, net	10,302	12,351
Customer Relationships and Loyalty Card Holders [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Amortizable Intangible Assets	1,867	2,139
Accumulated amortization	275	173
Purchased Prescription Files [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Amortizable Intangible Assets	932	885
Accumulated amortization	600	470
Favorable Lease Interests and Non-compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Amortizable Intangible Assets	619	594
Accumulated amortization	388	299
Trade Names and Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Amortizable Intangible Assets	532	675
Accumulated amortization	105	83
Total Indefinite-Lived intangible assets	5,604	6,590
Purchasing and Payer Contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Amortizable Intangible Assets	94	94
Accumulated amortization	71	65
Pharmacy Licenses [Member]
Finite-Lived Intangible Assets [Line Items]
Total Indefinite-Lived intangible assets	$ 2,093	$ 2,464