Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount of cash outflow for the payment of debt classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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Long-Term Debt (Debt Repayments) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Repurchases and repayments of debt	$ 6,364	$ 3,052	$ 4,378
NBCUniversal Media LLC [Member]
Debt Instrument [Line Items]
Repurchases and repayments of debt	3,498	$ 1,565	$ 1,022
Universal Studios Japan Term Loans [Member]
Debt Instrument [Line Items]
Repurchases and repayments of debt	3,347
Other Long-Term Debt [Member]
Debt Instrument [Line Items]
Repurchases and repayments of debt	179
Senior Notes [Member] \| Senior 6.30% Notes Due 2017 [Member]
Debt Instrument [Line Items]
Repurchases and repayments of debt	$ 1,000
Interest rate	6.30%
Senior Notes [Member] \| Senior 6.50% Notes Due 2017 [Member]
Debt Instrument [Line Items]
Repurchases and repayments of debt	$ 1,000
Interest rate	6.50%
Senior Notes [Member] \| Senior 8.875% Notes Due 2017 [Member]
Debt Instrument [Line Items]
Repurchases and repayments of debt	$ 550
Interest rate	8.875%
Senior Notes [Member] \| Senior 5.00% Notes Due 2061 [Member]
Debt Instrument [Line Items]
Repurchases and repayments of debt	$ 288
Interest rate	5.00%