Shareholders' Equity - Dividends Declared (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	0 Months Ended
Feb. 27, 2015	Dec. 09, 2014	Jul. 30, 2014	Apr. 17, 2014	Feb. 06, 2014	Feb. 27, 2015	Dec. 09, 2014	Jul. 30, 2014	Apr. 17, 2014	Feb. 06, 2014	May 30, 2013
Stockholders' Equity Note [Abstract]
Declaration Date	Feb. 27, 2015	Dec. 09, 2014	Jul. 30, 2014	Apr. 17, 2014	Feb. 06, 2014
Dividend Per Share (in usd per share)						$ 0.115us-gaap_DividendsPayableAmountPerShare	$ 0.115us-gaap_DividendsPayableAmountPerShare	$ 0.115us-gaap_DividendsPayableAmountPerShare	$ 0.115us-gaap_DividendsPayableAmountPerShare	$ 0.10us-gaap_DividendsPayableAmountPerShare	$ 0.10us-gaap_DividendsPayableAmountPerShare
Record Date	Apr. 01, 2015	Jan. 02, 2015	Oct. 01, 2014	Jul. 01, 2014	Apr. 01, 2014
Total Amount	$ 229us-gaap_DividendsCommonStockCash	$ 234us-gaap_DividendsCommonStockCash	$ 239us-gaap_DividendsCommonStockCash	$ 237us-gaap_DividendsCommonStockCash	$ 209us-gaap_DividendsCommonStockCash
Payment Date	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 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 S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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

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- Definition

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

+ References

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- Definition

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

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- Definition

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

+ References

No definition available.

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