Supplemental Financial Information (Noncash Investing and Financing Activities)(Details) $ / shares in Units, $ in Millions	6 Months Ended
Jun. 30, 2016 USD ($) $ / shares
Dividends payable, amount	$ 663
Dividends payable, amount per share \| $ / shares	$ 0.275
Capital expenditures incurred but not yet paid	$ 1,200
NBCUniversal Media LLC [Member]
Capital expenditures incurred but not yet paid	$ 215

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 15
-Subparagraph a
-Article 7

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