Accumulated Other Comprehensive Income (Loss) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Nov. 30, 2014	Nov. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ 178	$ (98)
Other comprehensive income before reclassification adjustments	70	139
Amounts reclassified from accumulated OCI	0	0
Tax benefit (provision)	(26)us-gaap_OtherComprehensiveIncomeLossTax	(19)us-gaap_OtherComprehensiveIncomeLossTax
Net other comprehensive income (loss)	44	120
Balance	222	22
Post-retirement Liability [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	15	63
Other comprehensive income before reclassification adjustments	(2)	12
Amounts reclassified from accumulated OCI	0	0
Tax benefit (provision)	1	(4)
Net other comprehensive income (loss)	(1)	8
Balance	14	71
Unrecognized Gains on Available-for-Sale Investments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	107	1
Other comprehensive income before reclassification adjustments	157	84
Amounts reclassified from accumulated OCI	0	0
Tax benefit (provision)	(58)	0
Net other comprehensive income (loss)	99	84
Balance	206	85
Unrealized Loss on Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(27)	0
Other comprehensive income before reclassification adjustments	(20)	0
Amounts reclassified from accumulated OCI	0	0
Tax benefit (provision)	8	0
Net other comprehensive income (loss)	(12)	0
Balance	(39)	0
Alliance Boots OCI [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(100)	(59)
Other comprehensive income before reclassification adjustments	(16)	(52)
Amounts reclassified from accumulated OCI	0	0
Tax benefit (provision)	6	18
Net other comprehensive income (loss)	(10)	(34)
Balance	(110)	(93)
Foreign Currency Translation [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	183	(103)
Other comprehensive income before reclassification adjustments	(49)	95
Amounts reclassified from accumulated OCI	0	0
Tax benefit (provision)	17	(33)
Net other comprehensive income (loss)	(32)	62
Balance	$ 151	$ (41)

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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