v3.10.0.1
Long-Term Debt (Schedule of Debt Outstanding) (Details)
£ in Millions, $ in Millions, € in Billions, ¥ in Billions, ¥ in Billions
Dec. 31, 2018
USD ($)
Dec. 31, 2018
GBP (£)
Dec. 31, 2018
JPY (¥)
Dec. 31, 2018
CNY (¥)
Dec. 31, 2018
EUR (€)
Dec. 31, 2017
USD ($)
Dec. 31, 2017
GBP (£)
Dec. 31, 2017
JPY (¥)
Debt Instrument [Line Items]                
Debt issuance costs, premiums and discounts, net $ (1,702)         $ (1,943)    
Total debt 111,743         64,556    
Less: Current portion 4,398         5,134    
Long-term debt $ 107,345         59,422    
Interest rate 3.77% 3.77% 3.77% 3.77% 3.77%      
Commercial Paper [Member]                
Debt Instrument [Line Items]                
Commercial paper $ 675         903    
Interest rate 2.86% 2.86% 2.86% 2.86% 2.86%      
Revolving Bank Credit Facility [Member]                
Debt Instrument [Line Items]                
Credit facility $ 606         0    
Interest rate 1.13% 1.13% 1.13% 1.13% 1.13%      
Term Loans [Member]                
Debt Instrument [Line Items]                
Term loans $ 13,268         3,880    
Interest rate 1.85% 1.85% 1.85% 1.85% 1.85%      
Senior notes with maturities of 5 years or less, at face value [Member]                
Debt Instrument [Line Items]                
Senior notes $ 26,331         15,680    
Interest rate 3.48% 3.48% 3.48% 3.48% 3.48%      
Senior notes with maturities between 5 and 10 years, at face value [Member]                
Debt Instrument [Line Items]                
Senior notes $ 26,727         13,277    
Interest rate 3.64% 3.64% 3.64% 3.64% 3.64%      
Senior notes with maturities greater than 10 years, at face value [Member]                
Debt Instrument [Line Items]                
Senior notes $ 45,030         31,838    
Interest rate 4.68% 4.68% 4.68% 4.68% 4.68%      
Other Including Capital Lease Obligations [Member]                
Debt Instrument [Line Items]                
Other, including capital lease obligations $ 808         $ 921    
Sky Transaction Term Loan [Member]                
Debt Instrument [Line Items]                
Term loans | £   £ 5,600            
Universal Studios Japan Term Loans Maturing 2022 [Member]                
Debt Instrument [Line Items]                
Term loans | ¥     ¥ 390         ¥ 435
Universal Beijing Resort Term Loans [Member]                
Debt Instrument [Line Items]                
Term loans 569              
Sky Outstanding Indebtedness [Member]                
Debt Instrument [Line Items]                
Current Principal Balance Debt Assumed in Acquisition Not Subject to Guarantee 10,700              
Sky Outstanding Indebtedness - U.S. Dollar Denominated [Member]                
Debt Instrument [Line Items]                
Senior notes $ 3,200              
Sky Outstanding Indebtedness - Euro Denominated [Member]                
Debt Instrument [Line Items]                
Senior notes | €         € 4.9      
Sky Outstanding Indebtedness - Pounds Sterling Denominated [Member]                
Debt Instrument [Line Items]                
Senior notes | £   1,100            
Notes 5.50% Due 2029 [Member]                
Debt Instrument [Line Items]                
Senior notes | £   £ 625         £ 625  
Interest rate 5.50% 5.50% 5.50% 5.50% 5.50% 5.50% 5.50% 5.50%
NBCUniversal Media LLC [Member]                
Debt Instrument [Line Items]                
Debt issuance costs, premiums and discounts, net $ (36)         $ (32)    
Total debt 12,882         12,473    
Less: Current portion 151         198    
Long-term debt $ 12,731         12,275    
Interest rate 3.58% 3.58% 3.58% 3.58% 3.58%      
NBCUniversal Media LLC [Member] | Term Loans [Member]                
Debt Instrument [Line Items]                
Term loans $ 4,122         3,860    
Interest rate 1.30% 1.30% 1.30% 1.30% 1.30%      
NBCUniversal Media LLC [Member] | Senior notes with maturities of 5 years or less, at face value [Member]                
Debt Instrument [Line Items]                
Senior notes $ 5,000         4,000    
Interest rate 4.39% 4.39% 4.39% 4.39% 4.39%      
NBCUniversal Media LLC [Member] | Senior notes with maturities between 5 and 10 years, at face value [Member]                
Debt Instrument [Line Items]                
Senior notes $ 0         1,000    
Interest rate 0.00% 0.00% 0.00% 0.00% 0.00%      
NBCUniversal Media LLC [Member] | Senior notes with maturities greater than 10 years, at face value [Member]                
Debt Instrument [Line Items]                
Senior notes $ 2,759         2,759    
Interest rate 5.50% 5.50% 5.50% 5.50% 5.50%      
NBCUniversal Media LLC [Member] | 4.00% Notes Due 2049 To Comcast [Member]                
Debt Instrument [Line Items]                
Notes due 2049 to Comcast $ 610         610    
Interest rate 4.00% 4.00% 4.00% 4.00% 4.00%      
NBCUniversal Media LLC [Member] | Other Including Capital Lease Obligations [Member]                
Debt Instrument [Line Items]                
Other, including capital lease obligations $ 427         $ 276    
NBCUniversal Media LLC [Member] | Universal Studios Japan Term Loans Maturing 2022 [Member]                
Debt Instrument [Line Items]                
Term loans | ¥     ¥ 390         ¥ 435
NBCUniversal Media LLC [Member] | Universal Beijing Resort Term Loans [Member]                
Debt Instrument [Line Items]                
Term loans | ¥       ¥ 4