Income Taxes (Narrative) (Details) (USD $)	3 Months Ended	12 Months Ended
	Dec. 31, 2009	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Taxes [Abstract]
Unrecognized tax benefit	$ 6,000,000	$ 6,000,000	$ 6,000,000	$ 6,000,000
Changes in unrecognized tax benefit impact on effective tax rate		0
Income tax expense credit		0	30,000,000	36,000,000
Total increase in the valuation allowance		1,200,000,000	121,000,000	135,000,000
Non-cash income tax benefit from continuing operations	248,000,000			(248,000,000)
Alternative minimum tax credit carryforward		367,000,000	392,000,000
Federal net operating losses for regular tax purposes		7,000,000,000
Unrealized benefit related to the implementation of share-based compensation accounting guidance		666,000,000
Available for state income tax purposes net operating losses		3,800,000,000
Tax carryforward expiration year		2012
State income tax purposes net operating losses		9,000,000
Cash payments (refunds) for income taxes		$ 1,000,000	$ (32,000,000)	$ 6,000,000
Percentage of cumulative stock ownership changes among material shareholders limited for company's future use of NOLs		50.00%
Limitation of future use of net operating losses and tax credits (in years)		3