v3.3.1.900
Income Taxes Components of current and long-term deferred income taxes (Details) - USD ($)
$ in Millions
Dec. 31, 2015
Dec. 31, 2014
Current assets and liabilities [Member]    
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals [Abstract]    
Employee benefits   $ 148
Depreciation and amortization   0
Other accruals and adjustments   476
Deferred Tax Assets, Net, Classification [Abstract]    
United States federal income tax loss carryforwards   0
United States federal income tax credit carryforward   0
United States state and local tax loss carryforwards and tax credit carryforwards   0
Other foreign tax loss carryforward   0
Other foreign income tax credit carryforwards   0
Valuation allowance for income tax loss and income tax credit carryforwards   (24)
Other valuation allowance   (7)
Total deferred income taxes   593
Long-term assets and liabilities [Member]    
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals [Abstract]    
Employee benefits $ 808 773
Depreciation and amortization (1,824) (2,010)
Other accruals and adjustments 717 282
Deferred Tax Assets, Net, Classification [Abstract]    
United States federal income tax loss carryforwards 20 58
United States federal income tax credit carryforward 183 150
United States state and local tax loss carryforwards and tax credit carryforwards 63 76
Other foreign tax loss carryforward 2,265 2,112
Other foreign income tax credit carryforwards 70 49
Valuation allowance for income tax loss and income tax credit carryforwards (2,315) (2,134)
Other valuation allowance (15) (29)
Deferred Tax Liabilities, Net $ (28) $ (673)