Stockholders' Equity 1 (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Jun. 30, 2014	Jun. 30, 2013
Cash dividends
Declaration date	May 15, 2014	May 09, 2013
Dividend per share (in dollars per share)	$ 0.25	$ 0.25
Record date	May 29, 2014	May 23, 2013
Total amount	$ 111	$ 114
Payment date	Jun. 17, 2014	Jun. 11, 2013

Aggregate dividends declared during the period for each share of common stock outstanding.

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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+ References

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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