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

No definition available.

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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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Number of shares of equity interests issued or issuable to acquire entity.

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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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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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

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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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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			9 Months Ended		12 Months Ended
	Sep. 25, 2019	May 01, 2019	Jan. 02, 2019	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Proceeds from Divestiture of Businesses							$ 231.0	$ 0.0
Gain (Loss) on Disposition of Business				$ (0.0)		$ (0.0)	3.0	$ (0.0)
Finite-lived Intangible Assets Acquired							502.0
Goodwill, Ending Balance		$ 837.0		1,449.0	$ 612.0		1,449.0		$ 612.0
Raycom [Member]
Payments to Acquire Businesses, Gross			$ 2,840.0
Business Combination, Consideration Transferred, Total			3,660.0				3,677.0
Goodwill, Ending Balance			834.0
Business Acquisition, Goodwill, Expected Tax Deductible Amount			150.0
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual				274.0			819.0
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual				$ 63.0			112.0
Raycom [Member] \| Retransmission Agreements [Member]
Finite-lived Intangible Assets Acquired			$ 313.0
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life			4 years 4 months 24 days
Raycom [Member] \| Off-Market Favorable Lease [Member]
Finite-lived Intangible Assets Acquired			$ 76.0
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life			9 years
Raycom [Member] \| Network Affiliation Agreements [Member]
Finite-lived Intangible Assets Acquired			$ 48.0
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life			4 years
Raycom [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life			3 years
Raycom [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life			40 years
Raycom [Member] \| Common Stock [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares			11,500,000
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable			$ 170.0
Raycom [Member] \| Preferred Stock [Member] \| Series A Perpetual Preferred Stock [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares			650,000
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable			$ 650.0
KYOU-TV and WUPV-TV [Member]
Payments to Acquire Businesses, Gross			17.0
Business Combination, Consideration Transferred, Total							$ 17.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Gross Contractual Receivables above Their Fair Value			2.0
WWNY-TV, WNYF-CD, and KEYC-TV [Member]
Payments to Acquire Businesses, Gross		48.0
Goodwill, Ending Balance		$ 3.0
Sioux Falls Acquisition [Member]
Payments to Acquire Businesses, Gross	$ 32.5
WSWG-TV [Member]
Proceeds from Divestiture of Businesses									$ 8.5
Gain (Loss) on Disposition of Business					$ 4.8
Stations Acquired from Raycom [Member]
Gain (Loss) on Disposition of Business			$ (234.0)