v2.4.0.6
Income Taxes (Schedule Of Income Tax Expense (Benefit)) (Details) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
Income Taxes [Abstract]      
U.S. federal $ (143) $ 244 $ 45
Various states 20 16 18
Canada and various provinces (20) 256 178
Total current tax (benefit) expense (143) 516 241
U.S. federal 1,986 781 (1,846)
Various states 95 21 (111)
Canada and various provinces 218 (83) (57)
Total deferred tax expense (benefit) 2,299 719 (2,014)
Total income tax expense (benefit) $ 2,156 $ 1,235 $ (1,773)