Restructuring, Impairment, and Other Corporate Matters (Narrative) (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020 USD ($) market	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) market	Jun. 30, 2019 USD ($)
Indefinite-lived Intangible Assets [Line Items]
Restructuring charges	$ 134	$ 0	$ 336	$ 128
Merger-related costs	10	0	41	0
Other corporate matters	$ 14	7	14	57
Number of television markets, quantitative impairment test \| market	3
Impairment charges	$ 25	0		0
Depreciation of abandoned technology	$ 0	$ 0	$ 12	$ 0
FCC License Impairment Test [Member]
Indefinite-lived Intangible Assets [Line Items]
Number of markets lower than carrying value \| market	2		2
Intangible assets, written down to fair value	$ 216		$ 216
Carrying amount	$ 53		$ 53
Percentage of fair value in excess of carrying amount	7.00%		7.00%
Average market share period			5 years
TV Entertainment Segment [Member] \| Depreciation and Amortization [Member]
Indefinite-lived Intangible Assets [Line Items]
Impairment charges	$ 25		$ 25

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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