Annual report pursuant to Section 13 and 15(d)

Income Taxes - Net Operating Loss and Tax Credit Carryforwards (Details)

v3.6.0.2
Income Taxes - Net Operating Loss and Tax Credit Carryforwards (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Tax Credit Carryforward [Line Items]    
Deferred Tax Asset $ 3,125 $ 2,266
Operating Loss Carryforwards [Line Items]    
Deferred Tax Asset 9,199 $ 9,439
Net operating losses before benefit of federal deductions 2,300  
Valuation allowance before considering benefit of federal deductions 612  
General business credits    
Tax Credit Carryforward [Line Items]    
Deferred Tax Asset 3,053  
Valuation Allowance 0  
Net Deferred Tax Asset 3,053  
Foreign tax credits    
Tax Credit Carryforward [Line Items]    
Deferred Tax Asset 72  
Valuation Allowance (72)  
Net Deferred Tax Asset 0  
Net operating losses – U.S.    
Operating Loss Carryforwards [Line Items]    
Deferred Tax Asset 1,908  
Valuation Allowance 0  
Net Deferred Tax Asset 1,908  
Net operating losses – U.K. and other    
Operating Loss Carryforwards [Line Items]    
Deferred Tax Asset 411  
Valuation Allowance (311)  
Net Deferred Tax Asset 100  
Net operating losses – U.K. and other | UNITED KINGDOM    
Operating Loss Carryforwards [Line Items]    
Deferred Tax Asset 5,410  
Valuation Allowance 0  
Net Deferred Tax Asset 5,410  
Net operating losses – U.S. states    
Operating Loss Carryforwards [Line Items]    
Deferred Tax Asset 1,470  
Valuation Allowance (398)  
Net Deferred Tax Asset $ 1,072