v3.6.0.2
Investments (Schedule of Investments) (Details) - USD ($)
$ in Millions
Dec. 31, 2016
Dec. 31, 2015
Fair Value, Equity And Cost Method Investments [Line Items]    
Fair Value Method $ 198 $ 167
Equity method 2,376 678
Cost method 2,770 2,485
Total Investments 5,344 3,330
Less: Current investments 97 106
Noncurrent investments 5,247 3,224
Atairos [Member]    
Fair Value, Equity And Cost Method Investments [Line Items]    
Equity method 1,601 0
Hulu [Member]    
Fair Value, Equity And Cost Method Investments [Line Items]    
Equity method 225 184
Other Equity Method Investments [Member]    
Fair Value, Equity And Cost Method Investments [Line Items]    
Equity method 550 494
Air Touch [Member]    
Fair Value, Equity And Cost Method Investments [Line Items]    
Cost method 1,599 1,583
BuzzFeed [Member]    
Fair Value, Equity And Cost Method Investments [Line Items]    
Cost method 400 200
Other Cost Method Investments [Member]    
Fair Value, Equity And Cost Method Investments [Line Items]    
Cost method 771 702
NBCUniversal Media LLC [Member]    
Fair Value, Equity And Cost Method Investments [Line Items]    
Fair Value Method 6 10
Equity method 561 497
Cost method 696 458
Noncurrent investments 1,263 965
NBCUniversal Media LLC [Member] | Hulu [Member]    
Fair Value, Equity And Cost Method Investments [Line Items]    
Equity method 225 184
NBCUniversal Media LLC [Member] | Other Equity Method Investments [Member]    
Fair Value, Equity And Cost Method Investments [Line Items]    
Equity method 336 313
NBCUniversal Media LLC [Member] | BuzzFeed [Member]    
Fair Value, Equity And Cost Method Investments [Line Items]    
Cost method 400 200
NBCUniversal Media LLC [Member] | Other Cost Method Investments [Member]    
Fair Value, Equity And Cost Method Investments [Line Items]    
Cost method $ 296 $ 258