v3.20.4

Acquisitions, Dispositions And Other Adjustments (Dispositions Narrative) (Details) - USD ($) $ in Millions |  |  |  |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | ---
Nov. 06, 2020 | Oct. 31, 2020 | Oct. 13, 2020 | Dec. 31, 2018 | Jun. 30, 2019 | Apr. 30, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Cash proceeds from sale of businesses and interest in affiliates |  |  |  |  |  |  | $ 3,641 | $ 4,684 | $ 2,148
Debt guarantee, original amount covered |  |  | $ 1,100 |  |  |  |  |  |
Debt guarantee |  |  | $ 600 |  |  |  |  |  |
Payments to redeem cumulative preferred interest in subsidiary that held notes secured by proceeds of sale |  |  |  |  |  |  | $ 1,950 | $ 0 | 0
CME |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Percent of interest disposed |  |  | 65.30% |  |  |  |  |  |
Cash proceeds from sale of businesses and interest in affiliates |  |  | $ 1,100 |  |  |  |  |  |
Gain (loss) on sale of investment |  |  | $ 39 |  |  |  |  |  |
Discontinued Operations, Disposed of by Sale | Puerto Rico And U.S. Virgin Islands Operations |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Gain (loss) on sale of investment |  | $ (82) |  |  |  |  |  |  |
Consideration for completion of sale of operations |  | 1,950 |  |  |  |  |  |  |
Payments to redeem cumulative preferred interest in subsidiary that held notes secured by proceeds of sale | $ 1,950 | 1,950 |  |  |  |  |  |  |
Discontinued Operations, Disposed of by Sale | Puerto Rico And U.S. Virgin Islands Operations | Net Tax Liabilities |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Decrease in accounts payable and accrued liabilities due to removal of held-for-sale liabilities upon disposal |  | 500 |  |  |  |  |  |  |
Discontinued Operations, Disposed of by Sale | Puerto Rico And U.S. Virgin Islands Operations | FCC Licenses |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Decrease in other current assets due to removal of held-for-sale assets upon disposal |  | 1,100 |  |  |  |  |  |  |
Discontinued Operations, Disposed of by Sale | Puerto Rico And U.S. Virgin Islands Operations | Goodwill |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Decrease in other current assets due to removal of held-for-sale assets upon disposal |  | 250 |  |  |  |  |  |  |
Discontinued Operations, Disposed of by Sale | Puerto Rico And U.S. Virgin Islands Operations | Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Decrease in other current assets due to removal of held-for-sale assets upon disposal |  | $ 850 |  |  |  |  |  |  |
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Brookfield Infrastructure Partners |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Gain (loss) on sale of investment |  |  |  | $ 432 |  |  |  |  |
Proceeds from assets sold |  |  |  | 1,100 |  |  |  |  |
Property, plant and equipment |  |  |  | 298 |  |  |  |  | 298
Goodwill |  |  |  | $ 215 |  |  |  |  | $ 215
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Hudson Yards North Tower Holdings LLC |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Cash proceeds from sale of businesses and interest in affiliates |  |  |  |  | $ 2,081 |  |  |  |
Gain (loss) on sale of investment |  |  |  |  | $ (100) |  |  |  |
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Hulu |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Cash proceeds from sale of businesses and interest in affiliates |  |  |  |  |  | $ 1,430 |  |  |
Gain (loss) on sale of investment |  |  |  |  |  | $ 740 |  |  |

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