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Goodwill and Intangible Assets (Schedule of Change in Goodwill) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Goodwill [Roll Forward] |  |
Balance, beginning of period | $ 66,154 | $ 36,780
Goodwill | 279 | 29,925
Dispositions | (12) | (13)
Adjustments | 1,379 | (21)
Foreign currency translation | 925 | (517)
Balance, end of period | 68,725 | 66,154
NBCUniversal Media LLC [Member] |  |
Goodwill [Roll Forward] |  |
Balance, beginning of period | 24,118 | 23,989
Goodwill | 176 | 36
Dispositions | 0 | (8)
Adjustments | (104) | (21)
Foreign currency translation | 50 | 122
Balance, end of period | 24,240 | 24,118
Operating Segments [Member] | Cable Communications [Member] |  |
Goodwill [Roll Forward] |  |
Balance, beginning of period | 12,784 | 12,784
Goodwill | 86 | 0
Dispositions | 0 | 0
Adjustments | 2,166 | 0
Foreign currency translation | 38 | 0
Balance, end of period | 15,074 | 12,784
Operating Segments [Member] | Cable Networks [Member] |  |
Goodwill [Roll Forward] |  |
Balance, beginning of period | 13,407 | 13,427
Goodwill | 162 | 0
Dispositions | 0 | 0
Adjustments | 490 | (13)
Foreign currency translation | 8 | (7)
Balance, end of period | 14,067 | 13,407
Operating Segments [Member] | Cable Networks [Member] | NBCUniversal Media LLC [Member] |  |
Goodwill [Roll Forward] |  |
Balance, beginning of period | 13,407 | 13,427
Goodwill | 162 | 0
Dispositions | 0 | 0
Adjustments | (105) | (13)
Foreign currency translation | (2) | (7)
Balance, end of period | 13,462 | 13,407
Operating Segments [Member] | Broadcast Television [Member] |  |
Goodwill [Roll Forward] |  |
Balance, beginning of period | 843 | 806
Goodwill | 14 | 36
Dispositions | 0 | 0
Adjustments | 199 | 1
Foreign currency translation | 3 | 0
Balance, end of period | 1,059 | 843
Operating Segments [Member] | Broadcast Television [Member] | NBCUniversal Media LLC [Member] |  |
Goodwill [Roll Forward] |  |
Balance, beginning of period | 843 | 806
Goodwill | 14 | 36
Dispositions | 0 | 0
Adjustments | 0 | 1
Foreign currency translation | 0 | 0
Balance, end of period | 857 | 843
Operating Segments [Member] | Filmed Entertainment [Member] |  |
Goodwill [Roll Forward] |  |
Balance, beginning of period | 3,184 | 3,212
Goodwill | 0 | 0
Dispositions | 0 | (8)
Adjustments | 138 | (9)
Foreign currency translation | (1) | (11)
Balance, end of period | 3,321 | 3,184
Operating Segments [Member] | Filmed Entertainment [Member] | NBCUniversal Media LLC [Member] |  |
Goodwill [Roll Forward] |  |
Balance, beginning of period | 3,184 | 3,212
Goodwill | 0 | 0
Dispositions | 0 | (8)
Adjustments | 1 | (9)
Foreign currency translation | (3) | (11)
Balance, end of period | 3,182 | 3,184
Operating Segments [Member] | Theme Parks [Member] |  |
Goodwill [Roll Forward] |  |
Balance, beginning of period | 6,684 | 6,544
Goodwill | 0 | 0
Dispositions | 0 | 0
Adjustments | 0 | 0
Foreign currency translation | 55 | 140
Balance, end of period | 6,739 | 6,684
Operating Segments [Member] | Theme Parks [Member] | NBCUniversal Media LLC [Member] |  |
Goodwill [Roll Forward] |  |
Balance, beginning of period | 6,684 | 6,544
Goodwill | 0 | 0
Dispositions | 0 | 0
Adjustments | 0 | 0
Foreign currency translation | 55 | 140
Balance, end of period | 6,739 | 6,684
Operating Segments [Member] | Sky Limited [Member] |  |
Goodwill [Roll Forward] |  |
Balance, beginning of period | 29,250 | 0
Goodwill | 17 | 29,889
Dispositions | (12) | 0
Adjustments | (1,616) | 0
Foreign currency translation | 822 | (639)
Balance, end of period | 28,461 | 29,250
Corporate, Non-Segment [Member] |  |
Goodwill [Roll Forward] |  |
Balance, beginning of period | 2 | 7
Goodwill | 0 | 0
Dispositions | 0 | (5)
Adjustments | 2 | 0
Foreign currency translation | 0 | 0
Balance, end of period | $ 4 | $ 2

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