Annual report pursuant to Section 13 and 15(d)

Assets and Liabilities Measured at Fair Value (Details)

v3.8.0.1
Assets and Liabilities Measured at Fair Value (Details)
shares in Millions, $ in Millions
Dec. 31, 2017
USD ($)
Dec. 31, 2016
USD ($)
Jun. 23, 2016
USD ($)
Jun. 06, 2016
$ / item
shares
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Short term marketable securities $ 35 $ 118    
Available-for-sale securities 27 16    
Variable postpaid forward        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Debt Instrument, Face Amount     $ 259  
Forward Contracts        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Derivative, Floor Price | $ / item       38.90
Derivative, Cap Price | $ / item       98.96
Forward Contracts | Variable postpaid forward        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Debt Instrument, Face Amount     $ 259  
Trip Advisor | Forward Contracts        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Forward Contract Shares indexed | shares       7
Recurring        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Cash equivalents 32 53    
Short term marketable securities 35 118    
Available-for-sale securities 27 16    
Derivative Asset 75 51    
Recurring | Level 1        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Cash equivalents 23 53    
Recurring | Level 2        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Cash equivalents 9      
Short term marketable securities 35 118    
Available-for-sale securities 27 16    
Derivative Asset $ 75 $ 51