Income Taxes (Computation Of Income Tax Expense (Benefit)) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Tax Disclosure [Abstract]
Statutory income tax provision expense/(benefit)	$ (873)	$ (686)	$ (177)
State income tax expense/(benefit), net of federal tax effect	(35)	(32)	(2)
Meal expense	6	6	6
Bankruptcy administration expenses	26	0	0
Change in valuation allowance	858	697	127
Tax benefit resulting from OCI allocation	(569)	0	0
Income Tax Reconciliation, Other Adjustments	18	15	11
Income tax benefit	$ (569)	$ 0	$ (35)