Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Amount of unrealized gain (loss) on investment in marketable security.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Number Of Television Markets, Impaired

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Financial Instruments and Fair Value Measurements (Narrative) (Details) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2020 USD ($)	Jun. 30, 2020 market	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Derivative [Line Items]
Carrying value of notes and debentures	$ 19,600			$ 19,600		$ 17,980
Fair value of debt	23,300			23,300		20,600
Investments without readily determinable fair value	104			104		113
Unrealized gain				32
Proceeds from sale of marketable securities				146
Gain on marketable securities			$ 12		$ 78
Impairment charges	0		$ 0	25	$ 0
FCC License Impairment Test [Member]
Derivative [Line Items]
Number of markets lower than carrying value \| market		2
Depreciation and Amortization [Member] \| TV Entertainment Segment [Member]
Derivative [Line Items]
Impairment charges				25
Equity in Loss of Investee Companies, Net of Tax [Member]
Derivative [Line Items]
Impairment charge	9			$ 9
Cash Flow Hedging [Member] \| Foreign exchange contract [Member]
Derivative [Line Items]
Maximum derivative contract term				24 months
Notional amount of derivative	1,010			$ 1,010		1,440
Cash Flow Hedging [Member] \| Foreign exchange contract [Member] \| Future Production Costs [Member]
Derivative [Line Items]
Notional amount of derivative	578			578		833
Cash Flow Hedging [Member] \| Foreign exchange contract [Member] \| Other Foreign Currency [Member]
Derivative [Line Items]
Notional amount of derivative	$ 435			$ 435		$ 606