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Earnings Per Share (Tables) | 6 Months Ended
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Jun. 30, 2018
Text Block [Abstract] |
Schedule Of Basic And Diluted Earnings Per Share |
|  |  | Three Months Ended June 30, |  | Six Months Ended June 30,
In millions except per share amounts |  | 2018 |  | 2017 |  | 2018 |  |  | 2017
Basic earnings per share: |  |  |  |  |  |  |  |  |  |  |  |
Net income (loss) available to common shareholders |  | $ | (146) |  | $ | (1,229) |  | $ | (244) |  | $ | (1,301)
Basic weighted average shares (1) |  |  | 89.1 |  |  | 125.7 |  |  | 88.9 |  |  | 128.5
Net income (loss) per basic common share: |  | $ | (1.64) |  | $ | (9.78) |  | $ | (2.75) |  | $ | (10.13)
Diluted earnings per share: |  |  |  |  |  |  |  |  |  |  |  |
Net income (loss) available to common shareholders |  | $ | (146) |  | $ | (1,229) |  | $ | (244) |  | $ | (1,301)
Diluted weighted average shares |  |  | 89.1 |  |  | 125.7 |  |  | 88.9 |  |  | 128.5
Net income (loss) per diluted common share: |  | $ | (1.64) |  | $ | (9.78) |  | $ | (2.75) |  | $ | (10.13)
Potentially dilutive securities excluded from the calculation of |  |  |  |  |  |  |  |  |  |  |  |
diluted EPS because of antidilutive affect (2) |  |  | 1.4 |  |  | 14.8 |  |  | 1.4 |  |  | 14.8
_________ |  |  |  |  |  |  |  |  |  |  |  |
(1) - Includes 0.8 million and 0.3 million of participating securities that met the service condition and were eligible to receive nonforfeitable dividends or dividend equivalents for the three and six months ended June 30, 2018 and 2017, respectively.
(2) - Includes securities that if exercised or vested would be net share settled resulting in a significantly lower impact to the outstanding share balance.

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