v3.7.0.1

Condensed Consolidating Financial Information (Narrative) (Details) $ in Millions | Mar. 31, 2017 USD ($)
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NBCUniversal Enterprise Senior Debt Securities [Member] |
Debt Instrument [Line Items] |
Principal amount of debt securities subject to guarantee | $ 3,300
Comcast Holdings' ZONES due October 2029 [Member] |
Debt Instrument [Line Items] |
Principal amount of debt securities subject to guarantee | 185
Comcast Holdings' ZONES due November 2029 [Member] |
Debt Instrument [Line Items] |
Principal amount of debt securities not subject to guarantee | 62
Universal Studios Japan Term Loans [Member] |
Debt Instrument [Line Items] |
Principal amount of debt securities not subject to guarantee | $ 3,400

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- Details
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