Share Repurchase Programs (Details) (USD $) In Billions, except Share data in Millions, unless otherwise specified	0 Months Ended	3 Months Ended	9 Months Ended
Sep. 19, 2012 Repurchase Program 2012 [Member]	Dec. 17, 2013 Repurchase Program 2013 [Member]	Sep. 30, 2014 Repurchase Program 2013 [Member]	Sep. 30, 2014 Repurchase Program 2013 [Member]
Equity, Class of Treasury Stock [Line Items]
Maximum authorization under share repurchase program	$ 6.0	$ 6.0
Repurchase of common stock (in shares)			10.2	37.2
Value of stock repurchased in the period			0.8	2.8
Remaining authorized repurchase amount				$ 3.9

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

+ Details

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- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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