Long-Term Debt (Narrative) (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Debt Instrument [Line Items]
Total carrying value of debt	$ 107,600
Total fair value of debt	118,500
Borrowings	363	$ 4,279
Repayments of debt	4,156	4,347
NBCUniversal Media LLC [Member]
Debt Instrument [Line Items]
Total carrying value of debt	13,400
Total fair value of debt	14,200
Borrowings	426	245
Repayments of debt	91	$ 332
Universal Beijing Resort Term Loans [Member]
Debt Instrument [Line Items]
Borrowings	363
Universal Beijing Resort Term Loans [Member] \| NBCUniversal Media LLC [Member]
Debt Instrument [Line Items]
Borrowings	363
Universal Studios Japan Term Loans Maturing 2022 [Member] \| NBCUniversal Media LLC [Member]
Debt Instrument [Line Items]
Repayments of debt	$ 73

Amount of short-term and long-term debt and lease obligation.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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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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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
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Amount of cash outflow for the payment of debt classified as other.

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