Share Repurchases (Narrative) (Details) (2013 Share Repurchase Program [Member], USD $) In Billions, unless otherwise specified	0 Months Ended	3 Months Ended
Jun. 06, 2013	Apr. 30, 2014
2013 Share Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Share Repurchase Program, Authorized Amount	$ 15.0
Stock Repurchase Program, Remaining Authorized Repurchase Amount		$ 10.7

Amount remaining of a stock repurchase plan authorized by an entity's Board of Directors.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration