v3.10.0.1
Income Taxes (Federal Statutory) (Details) - USD ($)
$ in Millions
3 Months Ended 12 Months Ended
Dec. 31, 2017
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Income Taxes [Line Items]        
Federal tax at statutory rate   $ 3,201 $ 5,374 $ 5,014
State income taxes, net of federal benefit   212 299 373
Foreign income taxed at different rates   147 70 65
Nontaxable income attributable to noncontrolling interests   (20) (45) (128)
Other adjustments   (138) (229) (67)
Excess tax benefits recognized on share-based compensation   (75) (297) 0
Federal tax legislation $ (12,700) (120) (12,682) 0
Income tax expense (benefit)   3,380 (7,569) 5,298
Adjustments to uncertain and effectively settled tax positions, net [Member]        
Income Taxes [Line Items]        
Other adjustments   144 (62) 24
Accrued interest on uncertain and effectively settled tax positions, net [Member]        
Income Taxes [Line Items]        
Other adjustments   $ 29 $ 3 $ 17