v3.7.0.1

Long-Term Debt (Narrative) (Details) $ in Millions | Mar. 31, 2017 USD ($)
--- | ---
Debt Instrument [Line Items] |
Total debt | $ 61,800
Fair value of debt | 66,700
Amounts available under revolving credit facilities | 7,400
NBCUniversal Media LLC [Member] |
Debt Instrument [Line Items] |
Total debt | 11,700
Fair value of debt | $ 12,600
Ownership in cable holding company subsidiaries | 100.00%
NBCUniversal Enterprise [Member] | NBCUniversal Media LLC [Member] |
Debt Instrument [Line Items] |
Related party aggregate principal amount senior notes not subject to guarantee | $ 3,300
Related party credit facility not subject to guarantee | 1,500
Related party liquidation preference preferred stock not subject to guarantee | 725
Comcast Revolving Credit Facility [Member] | NBCUniversal Media LLC [Member] |
Debt Instrument [Line Items] |
Principal amount of debt securities subject to guarantee | 7,000
Comcast and CCCL Parent Debt Securities [Member] | NBCUniversal Media LLC [Member] |
Debt Instrument [Line Items] |
Principal amount of debt securities subject to guarantee | 45,500
NBCUniversal Enterprise Credit Facility [Member] |
Debt Instrument [Line Items] |
Amounts available under revolving credit facilities | 585
Commercial Paper [Member] |
Debt Instrument [Line Items] |
Commercial paper | 0
NBCUniversal Enterprise Commercial Paper [Member] |
Debt Instrument [Line Items] |
Commercial paper | 915
Universal Studios Japan Term Loans [Member] |
Debt Instrument [Line Items] |
Non Guarantee Obligations Current Principal Balance | 3,400
Universal Studios Japan Term Loans [Member] | NBCUniversal Media LLC [Member] |
Debt Instrument [Line Items] |
Non Guarantee Obligations Current Principal Balance | $ 3,400

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