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Earnings Per Share (Tables) | 9 Months Ended
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Sep. 30, 2017
Text Block [Abstract] |
Schedule Of Basic And Diluted Earnings Per Share |
|  |  | Three Months Ended September 30, |  | Nine Months Ended September 30,
In millions except per share amounts |  | 2017 |  | 2016 |  | 2017 |  |  | 2016
Basic earnings per share: |  |  |  |  |  |  |  |  |  |  |  |
Net income (loss) |  | $ | (267) |  | $ | 31 |  | $ | (1,568) |  | $ | (73)
Less: undistributed earnings allocated to participating securities |  |  | - |  |  | 1 |  |  | - |  |  | -
Net income (loss) available to common shareholders |  |  | (267) |  |  | 30 |  |  | (1,568) |  |  | (73)
Basic weighted average shares (1) |  |  | 123.0 |  |  | 131.6 |  |  | 126.6 |  |  | 133.4
Net income (loss) per basic common share: |  | $ | (2.17) |  | $ | 0.23 |  | $ | (12.38) |  | $ | (0.55)
Diluted earnings per share: |  |  |  |  |  |  |  |  |  |  |  |
Net income (loss) |  | $ | (267) |  | $ | 31 |  | $ | (1,568) |  | $ | (73)
Less: undistributed earnings allocated to participating securities |  |  | - |  |  | 1 |  |  | - |  |  | -
Net income (loss) available to common shareholders |  |  | (267) |  |  | 30 |  |  | (1,568) |  |  | (73)
Basic weighted average shares (1) |  |  | 123.0 |  |  | 131.6 |  |  | 126.6 |  |  | 133.4
Effect of common stock equivalents: |  |  |  |  |  |  |  |  |  |  |  |
| Stock options |  |  | - |  |  | 0.4 |  |  | - |  |  | -
Diluted weighted average shares |  |  | 123.0 |  |  | 132.0 |  |  | 126.6 |  |  | 133.4
Net income (loss) per diluted common share: |  | $ | (2.17) |  | $ | 0.23 |  | $ | (12.38) |  | $ | (0.55)
Potentially dilutive securities excluded from the calculation of |  |  |  |  |  |  |  |  |  |  |  |
diluted EPS because of antidilutive affect |  |  | 14.4 |  |  | 16.1 |  |  | 14.4 |  |  | 17.3
_________ |  |  |  |  |  |  |  |  |  |  |  |
(1) - Includes 0.3 million and 0.9 million of participating securities that met the service condition and were eligible to receive nonforfeitable dividends or dividend equivalents for the three months ended September 30, 2017 and 2016, respectively. Includes 0.3 million and 0.9 million of participating securities that met the service condition and were eligible to receive nonforfeitable dividends or dividend equivalents for the nine months ended September 30, 2017 and 2016, respectively.

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- Definition Schedule of Basic and Diluted Earnings Per Share [Table Text Block] + References No definition available. + Details
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