v3.5.0.2

Long-term Debt (Debt Repayments) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Repurchases and repayments of debt	$ 2,551	$ 3,666
NBCUniversal Media LLC [Member]
Repurchases and repayments of debt	1,083	$ 1,003
Senior 2.875% Notes Due 2016 [Member]
Repurchases and repayments of debt	$ 1,000
Interest rate	2.875%
Maturity date	2016
Senior 2.875% Notes Due 2016 [Member] | NBCUniversal Media LLC [Member]
Repurchases and repayments of debt	$ 1,000
Interest rate	2.875%
Maturity date	2016
Senior 4.95% Notes Due 2016 [Member]
Repurchases and repayments of debt	$ 750
Interest rate	4.95%
Maturity date	2016
NBCUniversal Enterprise Senior Notes Due 2016 [Member]
Repurchases and repayments of debt	$ 700
Maturity date	2016

X

- Definition

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

+ References

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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

+ References

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)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The cash outflow for the payment of other borrowing not otherwise defined in the taxonomy.

+ 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=56944662&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

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

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X

- Details

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X

- Details

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Data Type:	na
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