v3.7.0.1

Significant Transactions (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions |  |  | 3 Months Ended
--- | --- | --- | ---
Apr. 06, 2017 | Aug. 22, 2016 | Mar. 31, 2017
DreamWorks Animation [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Cash consideration transferred |  | $ 3,773 |
Business acquisition, price paid per share (in dollars per share) |  | $ 41 |
Universal Studios Japan [Member] | Subsequent Event [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Payments to acquire additional interest in noncontrolling interest | $ 2,300 |  |
NBCUniversal Media LLC [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Contribution from member |  |  | $ 662
NBCUniversal Media LLC [Member] | DreamWorks Animation [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Cash consideration transferred |  | $ 3,773 |
NBCUniversal Media LLC [Member] | DreamWorks Animation [Member] | Member's contribution that represented Deferred Income Tax Assets and Other Tax-related Items recorded by Parent but excluded from net assets contributed [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Contribution from member |  | 281 |
NBCUniversal Media LLC [Member] | DreamWorks Animation [Member] | Tax Receivable Agreement [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Contribution from member |  | 146 |
NBCUniversal Media LLC [Member] | DreamWorks Animation [Member] | Cash Consideration Transferred By Comcast [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Cash consideration transferred |  | $ 3,773 |
Business acquisition, price paid per share (in dollars per share) |  | $ 41 |
NBCUniversal Media LLC [Member] | Universal Studios Japan [Member] | Subsequent Event [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Payments to acquire additional interest in noncontrolling interest | $ 2,300 |  |

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