v3.5.0.2

Condensed Consolidating Financial Information (Narrative) (Details) $ in Millions | 6 Months Ended
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Jun. 30, 2016 USD ($)
Comcast Holdings' ZONES due October 2029 [Member] |
Debt Instrument, Maturity Date, Description | October 2029
Principal amount of debt securities subject to guarantee | $ 185
Comcast Holdings' ZONES due November 2029 [Member] |
Debt Instrument, Maturity Date, Description | November 2029
Principal amount of debt securities not subject to guarantee | $ 62
NBCUniversal Enterprise Senior Debt Securities [Member] |
Principal amount of debt securities subject to guarantee | 3,300
Universal Studios Japan Term Loans [Member] |
Principal amount of debt securities not subject to guarantee | $ 3,800

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