Supplementary Financial Information (Details) - USD ($) $ in Millions	12 Months Ended
	Aug. 31, 2016	Aug. 31, 2015	Aug. 31, 2014
Non-cash transactions [Abstract]
Non-cash transactions for debt assumed	$ 0	$ 9,000
Non-cash transaction for common stock issued in relation to the second step transaction		11,000
Business Acquisition [Line Items]
Consideration received	$ 401	439
Fair value of assets acquired		26,600
Liabilities assumed		20,000
Capital lease obligations			$ 322
Walgreens Boots Alliance [Member]
Business Acquisition [Line Items]
Purchase consideration transferred		$ 8,100
Ownership percentage		45.00%
Walgreens Boots Alliance Development GmbH [Member]
Business Acquisition [Line Items]
Consideration received		$ 2,600