v3.7.0.1

Share-Based Compensation (Recognized Share-Based Compensation Expense) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized share-based compensation expense	$ 124	$ 115
NBCUniversal Media LLC [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized share-based compensation expense	25	23
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized share-based compensation expense	74	70
Restricted Stock Units (RSUs) [Member] | NBCUniversal Media LLC [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized share-based compensation expense	20	18
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized share-based compensation expense	40	37
Stock Options [Member] | NBCUniversal Media LLC [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized share-based compensation expense	2	2
Employee Stock Purchase Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized share-based compensation expense	10	8
Employee Stock Purchase Plans [Member] | NBCUniversal Media LLC [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized share-based compensation expense	$ 3	$ 3

X

- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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X

- 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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- Details

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- Details

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- Details

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