The renewable term generally granted by the FCC for radio broadcasting licenses.

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Summary Of Significant Accounting Policies [Line Items]

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Weighted-average period before the next renewal of the company's FCC broadcasting licenses.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

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-Name Accounting Standards Codification
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Amount of lessee's right to use underlying asset under operating lease.

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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2019
Summary Of Significant Accounting Policies [Line Items]
Renewable terms of FCC broadcasting licenses	8 years
Weighted-average period before the next renewal of the Company's FCC broadcasting licenses	2 years 9 months 18 days
Operating Lease, Liability	$ 42,217,508
Operating Lease, Right-of-Use Asset	$ 39,768,910
Accounting Standards Update 2016-02 [Member]
Summary Of Significant Accounting Policies [Line Items]
Operating Lease, Liability			$ 43,100,000
Operating Lease, Right-of-Use Asset			38,800,000
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Retained Earnings			$ 900,000
Geographic Concentration Risk [Member] \| Sales Revenue, Net [Member] \| Boston, MA, Philadelphia, PA and Tampa-Saint Petersburg, FL [Member]
Summary Of Significant Accounting Policies [Line Items]
Radio stations contributed to net revenue	60.70%	58.80%