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Earnings Per Share (Tables) | 3 Months Ended
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Mar. 31, 2015
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Schedule Of Basic And Diluted Earnings Per Share |
|  |  |  | Three Months Ended March 31, |
| $ in millions except share and per share amounts |  | 2015 |  | 2014 |
| Basic earnings per share: |  |  |  |  |  |  |
|  | Net income (loss) |  | $ | 69 |  | $ | 256 |
|  | Less: undistributed earnings allocated to participating securities |  |  | 2 |  |  | 5 |
|  | Net income (loss) available to common shareholders |  |  | 67 |  |  | 251 |
|  | Basic weighted average shares (1) |  |  | 181,735,876 |  |  | 189,033,982 |
|  | Net income (loss) per basic common share |  | $ | 0.37 |  | $ | 1.33 |
| Diluted earnings per share: |  |  |  |  |  |  |
|  | Net income (loss) |  |  | 69 |  |  | 256 |
|  | Less: undistributed earnings allocated to participating securities |  |  | 2 |  |  | 5 |
|  | Net income (loss) available to common shareholders |  |  | 67 |  |  | 251 |
|  | Basic weighted average shares (1) |  |  | 181,735,876 |  |  | 189,033,982 |
|  | Effect of common stock equivalents: |  |  |  |  |  |  |
|  | Stock options |  |  | 1,000,539 |  |  | 1,229,766 |
|  | Diluted weighted average shares |  |  | 182,736,415 |  |  | 190,263,748 |
|  | Net income (loss) per diluted common share |  | $ | 0.37 |  | $ | 1.32 |
|  | (1) - Includes 678,568 and 405,961 of participating securities that met the service condition and were eligible to receive nonforfeitable dividends or dividend equivalents for the |
|  | three months ended March 31, 2015 and 2014, respectively. |

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