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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Acquisitions and Dispositions - Additional Information (Detail) - USD ($)							1 Months Ended	3 Months Ended		12 Months Ended
	Nov. 14, 2019	Oct. 25, 2019	Aug. 31, 2019	Mar. 28, 2019	Mar. 15, 2019	Sep. 27, 2018	Dec. 31, 2019	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Nov. 13, 2019	Jun. 18, 2018	Apr. 03, 2015	Apr. 04, 2014	Apr. 10, 2013
Business Acquisition [Line Items]
Gain on sale of assets										$ 20,657,360
Asset purchase agreement, cash purchase price										17,264,484	$ 39,520,000
Business acquisition,transaction expenses	$ 400,000
Proceeds from sale of assets										26,349,462
Business acquisition liabilitites assumed										$ 10,000,000
Equity Method Investment, Ownership Percentage													20.00%	20.00%	20.00%	20.00%
Transaction Costs	400,000
Renegades Holdings, Inc. [Member]
Business Acquisition [Line Items]
Equity Method Investment, Ownership Percentage							45.00%	45.00%		45.00%		45.00%
Augusta GA [Member]
Business Acquisition [Line Items]
Gain on sale of assets									$ 400,000
Proceeds from sale of assets				$ 500,000
Operating and Broadcast Rights [Member] \| Clearwire [Member]
Business Acquisition [Line Items]
Gain on cancelation of license									$ 3,100,000
Proceeds from cancellation of license					$ 3,300,000
Land [Member] \| Las Vegas NV [Member]
Business Acquisition [Line Items]
Gain on sale of assets								$ 7,900,000
Proceeds from sale of assets										$ 13,500,000
Land [Member] \| Boca Raton, FL [Member]
Business Acquisition [Line Items]
Gain on sale of assets								6,500,000
Proceeds from sale of assets							$ 7,100,000
Radio Tower Member [Member] \| Tampa FL And New Jersey Member [Member]
Business Acquisition [Line Items]
Gain on sale of assets								$ 2,000,000
Proceeds from sale of assets		$ 2,400,000
WXTU-FM [Member]
Business Acquisition [Line Items]
Asset purchase agreement, cash purchase price						$ 38,000,000
Business acquisition partially financed by borrowings						35,000,000
Business acquisition partially funded in cash						3,000,000
Business acquisition,transaction expenses						100,000
Transaction Costs						$ 100,000
WDMK [Member]
Business Acquisition [Line Items]
Asset purchase agreement, cash purchase price			$ 13,500,000
Business acquisition partially financed by borrowings			10,000,000
Business acquisition partially funded in cash			3,500,000
Business acquisition,transaction expenses			300,000
Transaction Costs			$ 300,000
Out Laws [Member]
Business Acquisition [Line Items]
Business acquisition acquisition of ownership interest												80.00%
Business combination contingent payment agreed	3,600,000
Out Laws [Member] \| Franchise Fees Payable [Member]
Business Acquisition [Line Items]
Business acquisition liabilitites assumed	$ 10,000,000