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Earnings Per Share - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified | 3 Months Ended
--- | ---
Mar. 31, 2014 | Mar. 31, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |
Weighted Average number of shares outstanding dilutive effect |  | 3
Number of weighted average outstanding diluted shares | 1,101 | 1,169
5.25% Convertible Notes, Due 2014 [Member] |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |
Number of shares, option exercised | 89 |
Number of shares that become outstanding | 89 |
Number of weighted average outstanding shares included in both basic and diluted shares | 23 |
Weighted Average number of shares outstanding dilutive effect | 89 |
Number of weighted average outstanding diluted shares | 66 |
Convertible Notes [Member] |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |
Shares that would have been included in diluted earnings per share calculation | 66 |
Number of anti-dilutive securities | 66 |
Stock Awards [Member] |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |
Shares that would have been included in diluted earnings per share calculation | 18 |
Number of anti-dilutive securities | 10 |
Stock Option [Member] |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |
Shares that would have been included in diluted earnings per share calculation | 31 |
Number of anti-dilutive securities | 5 |
Weighted average exercise price of options | $ 14.53 | $ 12.20
Equity Unit Purchase Agreements [Member] |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |
Number of anti-dilutive securities | 10 | 31

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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Antidilution -URI http://asc.fasb.org/extlink&oid=6505113 Reference 3: 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 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Contingent Stock Agreement -URI http://asc.fasb.org/extlink&oid=6508534 + Details
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