Share Repurchases (Narrative) (Details) (USD $) In Billions	4 Months Ended	6 Months Ended
Jun. 02, 2011 2010 Share Repurchase Program [Member]	Jul. 31, 2011 2011 Share Repurchase Program [Member]
Share repurchase program, authorized amount	$ 15.0	$ 15.0
Share repurchase program, remaining authorized repurchase amount	$ 2.1

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us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount

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