Goodwill (Schedule of Change in Goodwill) (Details) $ in Millions	9 Months Ended
Sep. 30, 2019 USD ($)
Goodwill [Roll Forward]
Balance, beginning of period	$ 66,154
Acquisitions	154
Dispositions	(12)
Adjustments	1,440
Foreign currency translation	(823)
Balance, end of period	66,913
Corporate, Non-Segment [Member]
Goodwill [Roll Forward]
Balance, beginning of period	2
Acquisitions	0
Dispositions	0
Adjustments	2
Foreign currency translation	0
Balance, end of period	4
Cable Communications [Member] \| Operating Segments [Member]
Goodwill [Roll Forward]
Balance, beginning of period	12,784
Acquisitions	131
Dispositions	0
Adjustments	2,166
Foreign currency translation	(116)
Balance, end of period	14,965
Cable Networks [Member] \| Operating Segments [Member]
Goodwill [Roll Forward]
Balance, beginning of period	13,407
Acquisitions	0
Dispositions	0
Adjustments	490
Foreign currency translation	(34)
Balance, end of period	13,863
Broadcast Television [Member] \| Operating Segments [Member]
Goodwill [Roll Forward]
Balance, beginning of period	843
Acquisitions	13
Dispositions	0
Adjustments	199
Foreign currency translation	(11)
Balance, end of period	1,044
Filmed Entertainment [Member] \| Operating Segments [Member]
Goodwill [Roll Forward]
Balance, beginning of period	3,184
Acquisitions	0
Dispositions	0
Adjustments	138
Foreign currency translation	(11)
Balance, end of period	3,311
Theme Parks [Member] \| Operating Segments [Member]
Goodwill [Roll Forward]
Balance, beginning of period	6,684
Acquisitions	0
Dispositions	0
Adjustments	0
Foreign currency translation	106
Balance, end of period	6,790
Sky Limited [Member] \| Operating Segments [Member]
Goodwill [Roll Forward]
Balance, beginning of period	29,250
Acquisitions	10
Dispositions	(12)
Adjustments	(1,555)
Foreign currency translation	(757)
Balance, end of period	$ 26,936

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.

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