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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The cash outflow from the repayments of a long-term debt originally issued by another party but is assumed by the entity.

+ 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=66902209&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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Long-Term Debt (Debt Repayments) (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Apr. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Repurchases and repayments of debt		$ 3,052	$ 4,378	$ 3,175
NBCUniversal Media LLC [Member]
Debt Instrument [Line Items]
Repurchases and repayments of debt		1,565	$ 1,022	$ 906
Senior 2.875% Notes Due 2016 [Member]
Debt Instrument [Line Items]
Repurchases and repayments of debt		$ 1,000
Interest rate		2.875%
Senior 2.875% Notes Due 2016 [Member] \| NBCUniversal Media LLC [Member]
Debt Instrument [Line Items]
Repurchases and repayments of debt	$ 1,000
Interest rate	2.875%
Senior 4.95% Notes Due 2016 [Member]
Debt Instrument [Line Items]
Repurchases and repayments of debt		$ 750
Interest rate		4.95%
NBCUniversal Enterprise Senior Notes Due 2016 [Member]
Debt Instrument [Line Items]
Repurchases and repayments of debt		$ 700
DreamWorks Assumed Debt [Member]
Debt Instrument [Line Items]
Repayments of Assumed Debt		381
Other Long-Term Debt [Member]
Debt Instrument [Line Items]
Repurchases and repayments of debt		221
DreamWorks Animation [Member] \| NBCUniversal Media LLC [Member]
Debt Instrument [Line Items]
Repayments of Assumed Debt		$ 381