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Earnings Per Share (Tables) | 12 Months Ended
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Dec. 31, 2011
Earnings Per Share [Abstract] |
Schedule Of Basic And Diluted Earnings Per Share |
|  | Years Ended December 31, |
$ in millions except share and per share amounts |  | 2011 |  |  | 2010 |  |  | 2009 |
Net income (loss) |  | $ | (1,319 | ) |  | $ | 53 |  |  | $ | 634 |
Net income (loss) available to common shareholders |  | $ | (1,319 | ) |  | $ | 53 |  |  | $ | 623 |
Basic weighted average shares(1) |  |  | 197,019,968 |  |  |  | 202,421,433 |  |  |  | 208,156,622 |
Effect of common stock equivalents: |  |  |  |  |  |  |  |  |  |  |  |
Stock options |  |  | — |  |  |  | 599,701 |  |  |  | — |
Diluted weighted average shares |  |  | 197,019,968 |  |  |  | 203,021,134 |  |  |  | 208,156,622 |
Net income (loss) per common share: |  |  |  |  |  |  |  |  |  |  |  |
Basic |  | $ | (6.69 | ) |  | $ | 0.26 |  |  | $ | 2.99 |
Diluted |  | $ | (6.69 | ) |  | $ | 0.26 |  |  | $ | 2.99 |
(1)— | Includes 5,080,742, 5,325,428 and 5,259,561 of unvested restricted stock and units that receive nonforfeitable dividends or dividend equivalents for the years ended December 31, 2011, 2010 and 2009, respectively.

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