Goodwill and Other Intangible Assets, Schedule of Goodwill (Details) $ in Millions	9 Months Ended
	May 31, 2016 USD ($)
Goodwill [Roll Forward]
Net book value - Beginning Period	$ 16,372
Acquisitions	21
Other	4	[1]
Currency translation adjustments	(295)
Net book value - Ending Period	16,102
Retail Pharmacy USA [Member]
Goodwill [Roll Forward]
Net book value - Beginning Period	8,940
Acquisitions	0
Other	(4)	[1]
Currency translation adjustments	0
Net book value - Ending Period	8,936
Retail Pharmacy International [Member]
Goodwill [Roll Forward]
Net book value - Beginning Period	3,898
Acquisitions	21
Other	(5)	[1]
Currency translation adjustments	(151)
Net book value - Ending Period	3,763
Pharmaceutical Wholesale [Member]
Goodwill [Roll Forward]
Net book value - Beginning Period	3,534
Acquisitions	0
Other	13	[1]
Currency translation adjustments	(144)
Net book value - Ending Period	$ 3,403

[1] Other primarily represents immaterial purchase accounting adjustments for prior year Company acquisitions.