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Earnings Per Share (Tables) | 6 Months Ended
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Jun. 30, 2014
Text Block [Abstract] |
Schedule Of Basic And Diluted Earnings Per Share |
|  |  |  | Three Months Ended June 30, |  | Six Months Ended June 30, |
| $ in millions except share and per share amounts |  | 2014 |  | 2013 |  | 2014 |  | 2013 |
| Basic earnings per share: |  |  |  |  |  |  |  |  |  |  |  |  |
|  | Net income (loss) |  | $ | 120 |  | $ | (178) |  | $ | 376 |  | $ | (14) |
|  | Less: undistributed earnings allocated to participating securities |  |  | 4 |  |  | 0 |  |  | 10 |  |  | 0 |
|  | Net income (loss) available to common shareholders |  |  | 116 |  |  | (178) |  |  | 366 |  |  | (14) |
|  | Basic weighted average shares (1) |  |  | 189,169,042 |  |  | 189,163,527 |  |  | 189,101,884 |  |  | 189,135,587 |
|  | Net income (loss) per basic common share |  | $ | 0.61 |  | $ | (0.94) |  | $ | 1.93 |  | $ | (0.07) |
| Diluted earnings per share: |  |  |  |  |  |  |  |  |  |  |  |  |
|  | Net income (loss) |  |  | 120 |  |  | (178) |  |  | 376 |  |  | (14) |
|  | Less: undistributed earnings allocated to participating securities |  |  | 3 |  |  | 0 |  |  | 9 |  |  | 0 |
|  | Less: mark-to-market gain (loss) on warrants |  |  | 30 |  |  | 0 |  |  | 14 |  |  | 0 |
|  | Net income (loss) available to common shareholders |  |  | 87 |  |  | (178) |  |  | 353 |  |  | (14) |
|  | Basic weighted average shares (1) |  |  | 189,169,042 |  |  | 189,163,527 |  |  | 189,101,884 |  |  | 189,135,587 |
|  | Effect of common stock equivalents: |  |  |  |  |  |  |  |  |  |  |  |  |
|  | Stock options |  |  | 1,111,816 |  |  | 0 |  |  | 1,170,182 |  |  | 0 |
|  | Warrants |  |  | 2,626,013 |  |  | 0 |  |  | 2,779,370 |  |  | 0 |
|  | Diluted weighted average shares |  |  | 192,906,871 |  |  | 189,163,527 |  |  | 193,051,436 |  |  | 189,135,587 |
|  | Net income (loss) per diluted common share |  | $ | 0.45 |  | $ | (0.94) |  | $ | 1.83 |  | $ | (0.07) |
|  | (1) - Includes 270,443 and 549,265 of participating securities that met the service condition and were eligible to receive nonforfeitable dividends or dividend equivalents for the three months ended June 30, 2014 and 2013, respectively. Includes 337,827 and 628,692 of participating securities that met the service condition and were eligible to receive nonforfeitable dividends or dividend equivalents for the six months ended June 30, 2014 and 2013, 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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