Equity (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Common Stock, Shares, Outstanding beginning of period			75,362,956
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			$ 1,666
Net Income (Loss) Attributable to Parent	26	22	75	91
Common Stock, Shares, Outstanding end of period	75,527,281		75,527,281
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	1,701		1,701
Common Stock [Member]
Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures			164,325	24,685
Common Stock, Shares, Outstanding beginning of period			75,362,956	75,316,419
Common Stock, Shares, Outstanding end of period	75,527,281	75,341,104	75,527,281	75,341,104
Common Stock Including Additional Paid in Capital [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			836	831
Stock-based Compensation			1	1
Dividends, Common Stock			0	0
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders				0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	837	832	837	832
Accumulated Other Comprehensive Income (Loss) [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			(6)	(5)
Stock-based Compensation			0	0
Dividends, Common Stock			0	0
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders				0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(6)	(5)	(6)	(5)
Retained Earnings [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			833	766
Stock-based Compensation			0	0
Dividends, Common Stock			(41)	(39)
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders				0
Net Income (Loss) Attributable to Parent			75	91
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	867	818	867	818
Noncontrolling Interest [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			3	7
Stock-based Compensation			0	0
Dividends, Common Stock			0	0
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders				(4)
Net Income (Loss) Attributable to Noncontrolling Interest			0	0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 3	$ 3	$ 3	$ 3

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 19

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-04.22)

-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Other Comprehensive Income

-URI http://asc.fasb.org/extlink&oid=6519514

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.18)

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 130

-Paragraph 10, 15

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 20

-Article 9

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Net Income

-URI http://asc.fasb.org/extlink&oid=6518256

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 87-21

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 10: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28, 29, 30

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 11: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

Reference 12: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-04.19)

-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 13: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e565-108580

Reference 14: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph A7

-Appendix A

Reference 15: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 16: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

- Definition

Amount of Net Income (Loss) attributable to noncontrolling interest.

+ References+ Details

- Definition

Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

+ References+ Details

- Definition

Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

+ References+ Details