XML 136 R86.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - Fair Value, Measurements, Recurring - USD ($)
$ in Millions
Dec. 31, 2019
Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Short-term investments $ 1,308 $ 578
Net derivative contracts 5 (67)
Available for sale investments 0 12
Quoted Prices In Active Markets for Identical Assets (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Short-term investments 398 5
Net derivative contracts 0 0
Available for sale investments 0 12
Significant Other Observable Inputs (Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Short-term investments 910 573
Net derivative contracts 5 (67)
Available for sale investments 0 0
Total Cost Basis    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Short-term investments 1,308 578
Net derivative contracts 0 0
Available for sale investments $ 0 $ 7