Long-Term Debt (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Debt Instrument [Line Items]
Total debt	$ 109,100
Fair value of debt	115,800
Borrowings	222	$ 4,043
Repayments of debt	2,084	1,265
NBCUniversal Media LLC [Member]
Debt Instrument [Line Items]
Total debt	13,100
Fair value of debt	13,700
Borrowings	285	10
Repayments of debt	56	$ 55
Universal Beijing Resort Term Loans [Member] \| NBCUniversal Media LLC [Member]
Debt Instrument [Line Items]
Borrowings	222
Universal Studios Japan Term Loans Maturing 2022 [Member] \| NBCUniversal Media LLC [Member]
Debt Instrument [Line Items]
Repayments of debt	$ 45

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13,16)
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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Amount of cash outflow for the payment of debt classified as other.

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