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Earnings Per Share (Schedule Of Basic And Diluted Earnings Per Share) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Earnings Per Share
Stock options outstanding, antidilutive	3,803,310	5,589,498	3,815,395	5,483,258
Net income (loss)	$ 137,000,000	$ 1,295,000,000	$ (1,138,000,000)	$ (185,000,000)
Basic weighted-average shares	199,295,797	204,377,833	199,602,865	204,639,226
Effect of common stock equivalents: Stock options	$ 768,882	$ 543,840
Diluted weighted-average shares	200,064,679	204,921,673	199,602,865	204,639,226
Basic EPS: Net income (loss)	$ 0.69	$ 6.34	$ (5.70)	$ (0.90)
Diluted EPS: Net income (loss)	$ 0.68	$ 6.32	$ (5.70)	$ (0.90)
Unvested restricted stock and units that receive nonforfeitable dividends or dividend equivalents	5,035,256	5,463,932	5,102,013	5,424,146

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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