Goodwill Rollforward (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Goodwill beginning balance	$ 27,316	$ 27,098
Acquisitions	5,661	227
Adjustments	(32)	(9)
Goodwill ending balance	32,945	27,316
NBCUniversal Media LLC [Member]
Goodwill beginning balance	14,908	14,882
Acquisitions	5,487	35
Adjustments	(31)	(9)
Goodwill ending balance	20,364	14,908
Cable Communications [Member]
Goodwill beginning balance	12,217	12,206
Acquisitions	173	11
Adjustments	(1)	0
Goodwill ending balance	12,389	12,217
Cable Networks [Member]
Goodwill beginning balance	12,948	13,130
Acquisitions	17	20
Adjustments	(18)	(202)
Goodwill ending balance	12,947	12,948
Cable Networks [Member] \| NBCUniversal Media LLC [Member]
Goodwill beginning balance	12,948	13,130
Acquisitions	17	20
Adjustments	(18)	(202)
Goodwill ending balance	12,947	12,948
Broadcast Television [Member]
Goodwill beginning balance	767	769
Acquisitions	39	0
Adjustments	0	(2)
Goodwill ending balance	806	767
Broadcast Television [Member] \| NBCUniversal Media LLC [Member]
Goodwill beginning balance	767	769
Acquisitions	39	0
Adjustments	0	(2)
Goodwill ending balance	806	767
Filmed Entertainment [Member]
Goodwill beginning balance	211	1
Acquisitions	58	15
Adjustments	(2)	195
Goodwill ending balance	267	211
Filmed Entertainment [Member] \| NBCUniversal Media LLC [Member]
Goodwill beginning balance	211	1
Acquisitions	58	15
Adjustments	(2)	195
Goodwill ending balance	267	211
Theme Parks [Member]
Goodwill beginning balance	982	982
Acquisitions	5,373	0
Adjustments	(11)	0
Goodwill ending balance	6,344	982
Theme Parks [Member] \| NBCUniversal Media LLC [Member]
Goodwill beginning balance	982	982
Acquisitions	5,373	0
Adjustments	(11)	0
Goodwill ending balance	6,344	982
Corporate and Other [Member]
Goodwill beginning balance	191	10
Acquisitions	1	181
Adjustments	0	0
Goodwill ending balance	$ 192	$ 191

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
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