Share Repurchase Authorization Footnote (details) (Board of Directors Approved Repurchase Authorizations [Member], USD $) Share data in Millions, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2013
Board of Directors Approved Repurchase Authorizations [Member]
Repurchase activity
Number of shares repurchased (in shares)	3.7
Cost of shares repurchased	$ 300,000,000
Average cost per share	$ 81.01
Remaining capacity under share repurchase authorization	$ 1,860,000,000

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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