Broadcast Licenses - Schedule of Changes in Broadcasting Licenses (Detail) - USD ($) $ in Thousands  | 
9 Months Ended | 12 Months Ended | 
|---|---|---|
Sep. 30, 2022  | 
Dec. 31, 2021  | 
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| Indefinite-lived Intangible Assets [Line Items] | ||
| Balance, beginning of period before cumulative loss on impairment | $ 434,444 | $ 434,209 | 
| Accumulated loss on impairment, Beginning Balance | (114,436) | (114,436) | 
| Balance, beginning of period after cumulative loss on impairment | 320,008 | 319,773 | 
| Loss on impairment | (11,660) | 0 | 
| Balance, end of period before cumulative loss on impairment | 429,566 | 434,444 | 
| Accumulated loss on impairment, Ending Balance | (123,791) | (114,436) | 
| Balance, end of period after cumulative loss on impairment | 305,775 | 320,008 | 
| Radio Stations [Member] | ||
| Indefinite-lived Intangible Assets [Line Items] | ||
| Acquisitions of radio stations | 190 | $ 235 | 
| Dispositions of radio stations and FM translators | $ (2,763) | 
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- Definition Gross 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. No definition available. 
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- Definition Amount of accumulated impairment loss for an indefinite intangible asset representing future economic benefits arising from other assets acquired under a license agreement that are not individually identified and separately recognized. No definition available. 
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- Definition The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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- Definition Amount of divestiture of an asset lacking physical substance and having a projected indefinite period of benefit to fair value. Excludes financial assets and goodwill. No definition available. 
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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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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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. No definition available. 
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- Details 
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