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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) in the future that were not included in the computation of diluted EPS because to do so would increase EPS amounts or decrease loss per share amounts for the period presented.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Name Statement of Financial Accounting Standard (FAS)

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- Definition

Interest rate stated in the contractual debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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This element represents the income or loss from continuing operations attributable to the reporting entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items and cumulative effects of changes in accounting principles, but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests, if any.

+ References

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 29

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 28

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-Name Accounting Research Bulletin (ARB)

-Number 51

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-Subparagraph b(1)

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The amount of income (loss) from continuing operations per each share of common stock outstanding during the reporting period.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 21

-Article 9

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 128

-Paragraph 36, 37, 38

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 20

-Article 5

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 18

-Article 7

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The amount of income (loss) from continuing operations available to each share of common stock outstanding during the reporting period and each share that would have been outstanding assuming the issuance of common shares for all dilutive potential common shares outstanding during the reporting period.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 21

-Article 9

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 128

-Paragraph 11, 12, 36, 37, 38

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 128

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-Name Regulation S-X (SX)

-Number 210

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 18

-Article 7

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Aggregate awards of share options and nonvested shares to be issued to an employee under a share-based compensation arrangement are considered options for purposes of computing diluted earnings per share. Such share-based awards shall be considered to be outstanding as of the grant date for purposes of computing diluted earnings per share even though their exercise may be contingent upon vesting. Those share-based awards are included in the diluted Earnings Per Share (EPS) computation even if the employee may not receive (or be able to sell) the stock until some future date. Accordingly, all shares to be issued shall be included in computing diluted EPS if the effect is dilutive. The dilutive effect of share-based compensation arrangements shall be computed using the treasury stock method. If the equity share options or other equity instruments are outstanding for only part of a period, the shares issuable shall be weighted to reflect the portion of the period during which the equity instruments were outstanding.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 128

-Paragraph 20

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- Definition

Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 128

-Paragraph 9

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Net Income (Loss) Available to Common Stockholders plus adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 128

-Paragraph 11, 12

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The aggregate value of preferred stock dividends and other adjustments necessary to derive net income apportioned to common stockholders.

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No definition available.

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The average number of shares issued and outstanding that are used in calculating diluted EPS, determined based on the timing of issuance of shares in the period.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 128

-Paragraph 40

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Number of [basic] shares, after adjustment for contingently issuable shares and other shares not deemed outstanding, determined by relating the portion of time within a reporting period that common shares have been outstanding to the total time in that period.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 128

-Paragraph 171

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Earnings (Loss) Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Numerator for earnings per share, basic
Income (loss) from continuing operations attributable to controlling interest									$ (5,922)	$ 927	$ 3,207
Undistributed earnings allocable to participating securities										(5)	(18)
Income (loss) from continuing operations available to shareholders									(5,922)	922	3,189
Denominator for earnings per share, basic
Weighted-average shares outstanding	329	320	320	319	319	319	319	321	322	320	320
Weighted-average shares for per share calculation, basic	329	320	320	319	319	319	319	321	322	320	320
Per share earnings (loss) from continuing operations, basic									$ (18.40)	$ 2.88	$ 9.95
Numerator for earnings per share, diluted
Income (loss) from continuing operations attributable to controlling interest									(5,922)	927	3,207
Undistributed earnings allocable to participating securities										(5)	(18)
Income from continuing operations available to shareholders									$ (5,922)	$ 922	$ 3,189
Denominator for earnings per share, diluted
Weighted-average shares outstanding	329	320	320	319	319	319	319	321	322	320	320
Effect of dilutive securities:
Stock options and other share based awards (in shares)											1
Weighted-average shares for per share calculation, diluted	329	320	320	320	319	319	320	322	322	320	321
Per share earnings (loss) from continuing operations, diluted									$ (18.40)	$ 2.88	$ 9.92
1.625% Series A Convertible Senior Notes due December 2037
Anti-dilutive securities
Interest rate on convertible debt not having effect on earning per share calculation (as a percent)	1.625%								1.625%
1.50% Series B Convertible Senior Notes due December 2037
Anti-dilutive securities
Interest rate on convertible debt not having effect on earning per share calculation (as a percent)	1.50%								1.50%
1.50% Series C Convertible Senior Notes due December 2037
Anti-dilutive securities
Interest rate on convertible debt not having effect on earning per share calculation (as a percent)	1.50%								1.50%
Stock-based awards
Anti-dilutive securities
Share-based awards excluded from earnings per share calculation									2.4	2.2	1.7