Amount expected to be recognized in earnings for the specified restructuring cost.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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-Section 50
-Paragraph 1
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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Restructuring (Details) - USD ($) $ in Millions	12 Months Ended			24 Months Ended
Restructuring (Details) - USD ($) $ in Millions	Aug. 31, 2016	Aug. 31, 2015	Aug. 31, 2014	Aug. 31, 2016
Restructuring Reserve Disclosures [Abstract]
Total restructuring costs	$ 424	$ 559	$ 209
Retail Pharmacy USA [Member]
Restructuring Reserve Disclosures [Abstract]
Total restructuring costs	374	540	209
Retail Pharmacy International [Member]
Restructuring Reserve Disclosures [Abstract]
Total restructuring costs	29	19	0
Pharmaceutical Wholesale [Member]
Restructuring Reserve Disclosures [Abstract]
Total restructuring costs	21	0	0
Asset Impairments [Member]
Restructuring Reserve Disclosures [Abstract]
Total restructuring costs	225	223	137
Asset Impairments [Member] \| Retail Pharmacy USA [Member]
Restructuring Reserve Disclosures [Abstract]
Total restructuring costs	215	216	137
Asset Impairments [Member] \| Retail Pharmacy International [Member]
Restructuring Reserve Disclosures [Abstract]
Total restructuring costs	10	7	0
Asset Impairments [Member] \| Pharmaceutical Wholesale [Member]
Restructuring Reserve Disclosures [Abstract]
Total restructuring costs	0	0	0
Real Estate Costs [Member]
Restructuring Reserve Disclosures [Abstract]
Total restructuring costs	91	219	71
Real Estate Costs [Member] \| Retail Pharmacy USA [Member]
Restructuring Reserve Disclosures [Abstract]
Total restructuring costs	89	219	71
Real Estate Costs [Member] \| Retail Pharmacy International [Member]
Restructuring Reserve Disclosures [Abstract]
Total restructuring costs	1	0	0
Real Estate Costs [Member] \| Pharmaceutical Wholesale [Member]
Restructuring Reserve Disclosures [Abstract]
Total restructuring costs	1	0	0
Severance and Other Business Transition and Exit Costs [Member]
Restructuring Reserve Disclosures [Abstract]
Total restructuring costs	108	117	1
Severance and Other Business Transition and Exit Costs [Member] \| Retail Pharmacy USA [Member]
Restructuring Reserve Disclosures [Abstract]
Total restructuring costs	70	105	1
Severance and Other Business Transition and Exit Costs [Member] \| Retail Pharmacy International [Member]
Restructuring Reserve Disclosures [Abstract]
Total restructuring costs	18	12	0
Severance and Other Business Transition and Exit Costs [Member] \| Pharmaceutical Wholesale [Member]
Restructuring Reserve Disclosures [Abstract]
Total restructuring costs	20	0	$ 0
Lease Termination Costs [Member]
Restructuring Reserve Disclosures [Abstract]
Pre-tax charges incurred during the period		17
Cost Transformation Program [Member]
Restructuring Reserve Disclosures [Abstract]
Pre-tax charges incurred during the period	424	$ 542		$ 966
Cost Transformation Program [Member] \| Minimum [Member]
Restructuring Reserve Disclosures [Abstract]
Expected pre-tax charges	1,300			1,300
Cost Transformation Program [Member] \| Maximum [Member]
Restructuring Reserve Disclosures [Abstract]
Expected pre-tax charges	$ 1,500			1,500
Cost Transformation Program [Member] \| Asset Impairments [Member]
Restructuring Reserve Disclosures [Abstract]
Pre-tax charges incurred during the period				448
Cost Transformation Program [Member] \| Real Estate Costs [Member]
Restructuring Reserve Disclosures [Abstract]
Pre-tax charges incurred during the period				293
Cost Transformation Program [Member] \| Severance and Other Business Transition and Exit Costs [Member]
Restructuring Reserve Disclosures [Abstract]
Pre-tax charges incurred during the period				$ 225