Shareholders' Equity - Dividends Declared (Details) - USD ($) $ / shares in Units, $ in Millions	Jul. 30, 2015	May. 20, 2015	Feb. 27, 2015	Dec. 09, 2014	Jul. 30, 2014	Apr. 17, 2014	Feb. 06, 2014	May. 30, 2013
Declaration Date	Jul. 30, 2015	May 20, 2015	Feb. 27, 2015	Dec. 09, 2014	Jul. 30, 2014	Apr. 17, 2014	Feb. 06, 2014
Dividend Per Share (in usd per share)	$ 0.115	$ 0.115	$ 0.115	$ 0.115	$ 0.115	$ 0.115	$ 0.10	$ 0.10
Record Date	Oct. 01, 2015	Jul. 01, 2015	Apr. 01, 2015	Jan. 02, 2015	Oct. 01, 2014	Jul. 01, 2014	Apr. 01, 2014
Dividends, Common Stock, Cash	$ 229	$ 226	$ 229	$ 234	$ 239	$ 237	$ 209
Payment Date	Oct. 23, 2015	Jul. 23, 2015	Apr. 23, 2015	Jan. 23, 2015	Oct. 23, 2014	Jul. 23, 2014	Apr. 23, 2014

Date the declared dividend will be paid, in CCYY-MM-DD format.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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- Definition

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

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