Assets held for sale indefinite lived intangible assets reclassification.

No definition available.

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- Definition

Beneficial interest in trust reclassification.

+ References

No definition available.

+ Details

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- Definition

FCC broadcasting licenses.

+ References

No definition available.

+ Details

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- Definition

Amount of assets, excluding financial assets and goodwill, that lack physical substance, having a projected indefinite period of benefit, acquired at the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

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- Definition

Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date for the capitalized costs to acquire rights under a license arrangement (for example, to sell specified products in a specified territory) having an indefinite period of benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

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

+ References

No definition available.

+ Details

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- Details

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FCC Broadcasting Licenses - Carrying Amount of Broadcasting Licenses (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Nov. 01, 2016
FCC Broadcasting Licenses [Line Items]
Beginning Balance	$ 451,811,500
Ending Balance	489,186,679	$ 451,811,500
FCC Broadcasting License [Member]
FCC Broadcasting Licenses [Line Items]
Beginning Balance	451,811,500	228,554,165
Acquisitions of translator licenses	1,431,579	495,075
Assets held for sale reclassification		(24,759,640)
Beneficial interest in trust reclassification		(15,738,300)
Ending Balance	489,186,679	451,811,500
Greater Media Inc. [Member]
FCC Broadcasting Licenses [Line Items]
Assets acquisitions			$ 263,260,200
Greater Media Inc. [Member] \| FCC Broadcasting License [Member]
FCC Broadcasting Licenses [Line Items]
Assets acquisitions		$ 263,260,200
CBS Radio Stations Inc., Entercom Boston LLC and The Entercom Divestiture Trust [Member] \| FCC Broadcasting License [Member]
FCC Broadcasting Licenses [Line Items]
Assets acquisitions	$ 35,943,600