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Long-Term Debt (Narrative) (Details) - USD ($) $ in Millions | 6 Months Ended
--- | ---
Jun. 30, 2018 | Jun. 30, 2017
Debt Instrument [Line Items] |  |
Total debt | $ 64,600 |
Fair value of debt | 66,000 |
Repurchases and repayments of debt | 4,347 | $ 4,967
NBCUniversal Media LLC [Member] |  |
Debt Instrument [Line Items] |  |
Total debt | 12,500 |
Fair value of debt | 12,700 |
Repurchases and repayments of debt | 332 | $ 3,402
Universal Beijing Resort Term Loans [Member] | NBCUniversal Media LLC [Member] |  |
Debt Instrument [Line Items] |  |
Debt face amount | 235 |
Universal Studios Japan Term Loans [Member] |  |
Debt Instrument [Line Items] |  |
Repurchases and repayments of debt | 318 |
Universal Studios Japan Term Loans [Member] | NBCUniversal Media LLC [Member] |  |
Debt Instrument [Line Items] |  |
Repurchases and repayments of debt | $ 318 |

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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13,16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
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- Definition 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. + References No definition available. + Details
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- Definition 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. + References No definition available. + Details
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- Definition Amount of cash outflow for the payment of debt classified as other. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585 + Details
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- Details
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- Details
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