Goodwill Rollforward (Details) $ in Millions	6 Months Ended
Jun. 30, 2016 USD ($)
Goodwill beginning balance	$ 32,945
Acquisitions	165
Adjustments	(294)
Foreign currency translation	976
Goodwill ending balance	33,792
NBCUniversal Media LLC [Member]
Goodwill beginning balance	20,364
Acquisitions	92
Adjustments	(289)
Foreign currency translation	976
Goodwill ending balance	21,143
Cable Communications [Member]
Goodwill beginning balance	12,389
Acquisitions	73
Adjustments	176
Foreign currency translation	0
Goodwill ending balance	12,638
Cable Networks [Member]
Goodwill beginning balance	12,947
Acquisitions	0
Adjustments	0
Foreign currency translation	7
Goodwill ending balance	12,954
Cable Networks [Member] \| NBCUniversal Media LLC [Member]
Goodwill beginning balance	12,947
Acquisitions	0
Adjustments	0
Foreign currency translation	7
Goodwill ending balance	12,954
Broadcast Television [Member]
Goodwill beginning balance	806
Acquisitions	0
Adjustments	0
Foreign currency translation	0
Goodwill ending balance	806
Broadcast Television [Member] \| NBCUniversal Media LLC [Member]
Goodwill beginning balance	806
Acquisitions	0
Adjustments	0
Foreign currency translation	0
Goodwill ending balance	806
Filmed Entertainment [Member]
Goodwill beginning balance	267
Acquisitions	92
Adjustments	0
Foreign currency translation	12
Goodwill ending balance	371
Filmed Entertainment [Member] \| NBCUniversal Media LLC [Member]
Goodwill beginning balance	267
Acquisitions	92
Adjustments	0
Foreign currency translation	12
Goodwill ending balance	371
Theme Parks [Member]
Goodwill beginning balance	6,344
Acquisitions	0
Adjustments	(289)
Foreign currency translation	957
Goodwill ending balance	7,012
Theme Parks [Member] \| NBCUniversal Media LLC [Member]
Goodwill beginning balance	6,344
Acquisitions	0
Adjustments	(289)
Foreign currency translation	957
Goodwill ending balance	7,012
Corporate and Other [Member]
Goodwill beginning balance	192
Acquisitions	0
Adjustments	(181)
Foreign currency translation	0
Goodwill ending balance	$ 11

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
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-Section 45
-Paragraph 1
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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