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

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-Name Emerging Issues Task Force (EITF)

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-Paragraph 4

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Diluted Earnings Per Share

-URI http://asc.fasb.org/extlink&oid=6510752

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-Name Accounting Standards Codification

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-Name Accounting Standards Codification

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-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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+ Details

Earning Per Share - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2012	Jun. 30, 2011
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Participating securities outstanding, maximum	1	1	2
Stock And Performance Awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Participating securities outstanding, nonforfeitable	12	12	7
Equity Unit Purchase Agreements
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of anti-dilutive securities		28	19
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares that would have been included in diluted earnings per share calculation	19
Number of anti-dilutive securities	4
Weighted average exercise price of options		$ 15.44	$ 28.61
Convertible notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares that would have been included in diluted earnings per share calculation	89
Number of anti-dilutive securities	89	89
Stock awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares that would have been included in diluted earnings per share calculation	12
Number of anti-dilutive securities	6