Segment Information (Details 2) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Total consolidated operating income
Total consolidated operating income	$ 157	$ 169	$ 395	$ 470
Make-whole charge on repurchase and redemption of senior notes and write-off of debt issuance costs			(171)
Interest expense	(34)	(41)	(74)	(84)
Income before income taxes and interest in earnings of associates	$ 123	$ 128	$ 150	$ 386

Sum of operating profit and nonoperating income (expense) before income (loss) from equity method investments, income taxes, extraordinary items, cumulative effects of changes in accounting principles, and noncontrolling interest.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph h
-Subparagraph 1(i)
-Article 4

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- Definition

The cost of borrowed funds accounted for as interest that was charged against earnings during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 34
-Paragraph 21

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher OTS
-Name Federal Regulation (FR)
-Number Title 12
-Chapter V
-Section 563c.102
-Paragraph 9
-Subsection II

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 9
-Article 9

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The net result for the period of deducting operating expenses from operating revenues.

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Make-whole charge on repurchase and redemption of senior notes and write off of unamortized debt issuance costs.

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- Definition

Total Consolidated Operating Income.

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