v3.6.0.2
Property and Equipment (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Property, Plant and Equipment [Line Items]    
Property and equipment, at cost $ 85,947 $ 81,765
Less: Accumulated depreciation 49,694 48,100
Property and equipment, net 36,253 33,665
NBCUniversal Media LLC [Member]    
Property, Plant and Equipment [Line Items]    
Property and equipment, at cost 13,861 12,300
Less: Accumulated depreciation 3,350 2,779
Property and equipment, net $ 10,511 9,521
Cable Distribution System [Member]    
Property, Plant and Equipment [Line Items]    
Weighted-Average Original Useful Life 11 years  
Property and equipment, at cost $ 34,028 32,586
Customer Premise Equipment [Member]    
Property, Plant and Equipment [Line Items]    
Weighted-Average Original Useful Life 6 years  
Property and equipment, at cost $ 28,621 28,559
Other Equipment [Member]    
Property, Plant and Equipment [Line Items]    
Weighted-Average Original Useful Life 8 years  
Property and equipment, at cost $ 9,475 8,539
Building and Leasehold Improvements [Member]    
Property, Plant and Equipment [Line Items]    
Weighted-Average Original Useful Life 29 years  
Property and equipment, at cost $ 12,550 10,829
Building and Leasehold Improvements [Member] | NBCUniversal Media LLC [Member]    
Property, Plant and Equipment [Line Items]    
Weighted-Average Original Useful Life 30 years  
Property and equipment, at cost $ 7,543 6,543
Furniture, Fixtures and Equipment [Member] | NBCUniversal Media LLC [Member]    
Property, Plant and Equipment [Line Items]    
Weighted-Average Original Useful Life 11 years  
Property and equipment, at cost $ 4,158 3,457
Construction in Process [Member] | NBCUniversal Media LLC [Member]    
Property, Plant and Equipment [Line Items]    
Property and equipment, at cost 1,176 1,339
Land [Member]    
Property, Plant and Equipment [Line Items]    
Property and equipment, at cost 1,273 1,252
Land [Member] | NBCUniversal Media LLC [Member]    
Property, Plant and Equipment [Line Items]    
Property and equipment, at cost $ 984 $ 961