Represents the gross contractual receivables above their fair value recorded at acquisition date.

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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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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Amount of increase in assets, excluding financial assets and goodwill, lacking physical substance with an indefinite life, from an acquisition.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Note 3 - Acquisitions and Divestitures (Details Textual) - USD ($) $ in Millions									3 Months Ended	12 Months Ended
	Dec. 31, 2020	Nov. 02, 2020	Sep. 01, 2020	Jul. 31, 2020	Oct. 01, 2019	Sep. 25, 2019	May 01, 2019	Jan. 02, 2019	Dec. 31, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Combination, Acquisition Related Costs											$ 79
Finite-lived Intangible Assets Acquired										$ 40	522
Goodwill, Ending Balance	$ 1,460								$ 612	1,460	1,446	$ 612
Proceeds from Divestiture of Businesses										0	253	$ 9
Stations Acquired from Raycom [Member]
Gain (Loss) on Disposition of Business								$ 234
WCAV-TV and WVAW-TV [Member]
Gain (Loss) on Disposition of Business					$ 19
WSWG-TV [Member]
Gain (Loss) on Disposition of Business									$ 5
WSWG-TV [Member] \| Lockwood Broadcasting, Inc. [Member]
Proceeds from Divestiture of Businesses								9
Broadcast Licenses Acquired in 2020 [Member]
Indefinite-lived Intangible Assets Acquired										5
Alaska Transactions [Member]
Payments to Acquire Businesses, Gross				$ 19
Goodwill, Ending Balance	2									2
Columbus Acquisition [Member]
Payments to Acquire Businesses, Gross			$ 22
Goodwill, Ending Balance	1									1
Sioux Falls Acquisition [Member]
Payments to Acquire Businesses, Gross		$ 22				$ 33
Goodwill, Ending Balance	11				2					11	2
Lubbock Transactions [Member]
Payments to Acquire Businesses, Gross	23
The 2020 Acquisitions [Member]
Business Combination, Acquisition Related Costs										1
Goodwill, Ending Balance	$ 14									$ 14
The 2020 Acquisitions [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)										3 years
Finite-Lived Intangible Asset, Useful Life (Year)										1 year
The 2020 Acquisitions [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)										40 years
Finite-Lived Intangible Asset, Useful Life (Year)										4 years
Raycom [Member]
Payments to Acquire Businesses, Gross								2,840
Business Combination, Consideration Transferred, Total								3,660			3,677
Goodwill, Ending Balance								$ 829			829
Business Acquisition, Goodwill, Expected Tax Deductible Amount					150
Raycom [Member] \| Common Stock [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares)								11,500,000
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable								$ 170
Raycom [Member] \| Preferred Stock [Member] \| Series A Perpetual Preferred Stock [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares)								650,000
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable								$ 650
KYOU-TV and WUPV-TV [Member]
Payments to Acquire Businesses, Gross								17
Business Combination, Consideration Transferred, Total											17
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Gross Contractual Receivables above Their Fair Value								2
WWNY-TV, WNYF-CD, and KEYC-TV [Member]
Payments to Acquire Businesses, Gross							$ 48
Goodwill, Ending Balance							$ 3
Charlottesville Acquisition [Member]
Payments to Acquire Businesses, Gross					$ 13
Goodwill, Ending Balance											0
Acquisitions 2019 [Member]
Goodwill, Ending Balance											834
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual											1,100
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual											$ 198
Acquisitions 2019 [Member] \| Retransmission Agreements [Member]
Finite-lived Intangible Assets Acquired								$ 322
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year)								4 years 1 month 6 days
Acquisitions 2019 [Member] \| Off-Market Favorable Lease [Member]
Finite-lived Intangible Assets Acquired								$ 98
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year)								7 years 8 months 12 days
Acquisitions 2019 [Member] \| Network Affiliation Agreements [Member]
Finite-lived Intangible Assets Acquired								$ 50
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year)								3 years 8 months 12 days
Acquisitions 2019 [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)								3 years
Acquisitions 2019 [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)								40 years