CONSOLIDATED CONDENSED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) (USD $) In Millions, unless otherwise specified	3 Months Ended
Nov. 30, 2014	Nov. 30, 2013
CONSOLIDATED CONDENSED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) [Abstract]
Net Earnings	$ 836us-gaap_ProfitLoss	$ 704us-gaap_ProfitLoss
Other comprehensive income (loss), net of tax:
Postretirement liability	(1)	8
Changes in unrecognized gain on available-for-sale investments	99	84
Unrealized loss on cash flow hedges	(12)	0
Share of other comprehensive income of Alliance Boots	(10)	(34)
Cumulative translation adjustments	(32)	62
Total Other Comprehensive Income (Loss)	44	120
Total Comprehensive Income	880us-gaap_ComprehensiveIncomeNetOfTax	824us-gaap_ComprehensiveIncomeNetOfTax
Comprehensive income attributable to non-controlling interests	27	9
Comprehensive income attributable to Walgreen Co.	$ 853	$ 815

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of (increase) decrease in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount before tax, after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount before tax of other comprehensive (income) loss attributable to noncontrolling interests.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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