Goodwill and Other Intangible Assets, Schedule of Goodwill (Details) - USD ($) $ in Millions		12 Months Ended
		Aug. 31, 2015		Aug. 31, 2014
Goodwill [Roll Forward]
Net book value - Beginning Period		$ 2,359		$ 2,410
Acquisitions		14,972		58
Sale of business		(706)	[1]	(92)	[2]
Other	[3]	(3)		(17)
Currency translation adjustments		(250)
Net book value - Ending Period		16,372		2,359
Retail Pharmacy USA [Member]
Goodwill [Roll Forward]
Net book value - Beginning Period		2,359		2,410
Acquisitions		7,290		58
Sale of business		(706)	[1]	(92)	[2]
Other	[3]	(3)		(17)
Currency translation adjustments		0
Net book value - Ending Period		8,940		2,359
Retail Pharmacy International [Member]
Goodwill [Roll Forward]
Net book value - Beginning Period		0		0
Acquisitions		4,036		0
Sale of business		0	[1]	0	[2]
Other	[3]	0		0
Currency translation adjustments		(138)
Net book value - Ending Period		3,898		0
Pharmaceutical Wholesale [Member]
Goodwill [Roll Forward]
Net book value - Beginning Period		0		0
Acquisitions		3,646		0
Sale of business		0	[1]	0	[2]
Other	[3]	0		0
Currency translation adjustments		(112)
Net book value - Ending Period		$ 3,534		$ 0

[1] Represents goodwill associated with Walgreens Infusion Services business which was sold in April 2015.

[2] Represents goodwill associated with Walgreens Take Care Employer business which was sold in June 2014.

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