v3.3.1.900

Condensed Consolidating Financial Information (Narrative) (Details) - USD ($) $ in Millions |  | 12 Months Ended
--- | --- | ---
Nov. 13, 2015 | Dec. 31, 2015
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
Guarantor Subsidiaries [Member] |  |
Principal amount of debt securities subject to guarantee |  | 44,300
Maturing In Next Five Years [Member] |  |
Principal amount of debt securities subject to guarantee |  | $ 10,700
NBCUniversal Enterprise Credit Facility [Member] |  |
Debt Instrument, Maturity Date, Description |  | March 2018
NBCUniversal Enterprise Senior Debt Securities [Member] |  |
Principal amount of debt securities subject to guarantee |  | $ 4,000
Universal Studios Japan Term Loans [Member] |  |
Debt Instrument, Maturity Date, Description | November 2020 |
Principal amount of debt securities not subject to guarantee |  | $ 3,300

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