Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies - Additional Information (Detail)

v3.20.4
Summary of Significant Accounting Policies - Additional Information (Detail)
 12 Months Ended
Dec. 31, 2020
USD ($)
shares
Dec. 31, 2019
USD ($)
Segments
shares
Dec. 31, 2018
USD ($)
May 19, 2017
USD ($)
Summary Of Significant Accounting Policies [Line Items]        
Interest Costs Capitalized $ 27,000,000,000 $ 200,000    
Capitalized computer software, additions 3,400,000 2,700,000    
Capitalized computer software, amortization 2,800,000 2,600,000    
Impairment of intangible assets, finite-lived 0      
Carrying value of notes 216,300,000      
Debt related commitment fees and debt issuance costs 6,300,000      
Debt issuance costs, gross 900,000      
Increase in Valuation Allowance Deferred Tax Asset 35,100,000 35,100,000    
Deferred Tax Assets Valuation Allowance 48,073,000 12,977,000    
Business combination recognized identifiable assets increase or decrease   $ 100,000    
Debt instrument, estimated fair value $ 199,000,000      
Option to purchase shares of common stock outstanding | shares 2,291,020 1,860,722    
Percentage of total revenue 30.70% 35.30%    
Self-insurance reserve $ 543,000 $ 640,000 $ 828,000  
Deferred tax assets operating loss carry forwards domestic 28,400,000      
Deferred tax assets other financial statement accrual assets 4,000,000      
Domestic Tax Authority [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Deferred Tax Assets Valuation Allowance 28,400,000 8,900,000    
State and Local Jurisdiction [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Deferred Tax Assets Valuation Allowance 15,700,000 4,100,000    
Accounting Standards Update 2016-01 [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Liability recognised for Tax Position   300,000    
Combination of Seven Radio Station [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Discontinued operation, gain (loss) from disposal of discontinued operation, before income tax $ 1,400,000 $ 9,400,000    
Number Of Radio Stations | Segments   9    
Combination of Three Station [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Discontinued operation, gain (loss) from disposal of discontinued operation, before income tax   $ 4,700,000    
Washington radio stations [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Discontinued operation, gain (loss) from disposal of discontinued operation, before income tax   3,800,000    
Florida radio stations [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Discontinued operation, gain (loss) from disposal of discontinued operation, before income tax   1,600,000    
WBZW-AMFlorida radio stations [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Discontinued operation, gain (loss) from disposal of discontinued operation, before income tax   1,500,000    
Combination of Two Station [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Discontinued operation, gain (loss) from disposal of discontinued operation, before income tax   1,300,000    
MikeTurner [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Discontinued operation, gain (loss) from disposal of discontinued operation, before income tax   200,000    
Human Event [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Discontinued operation, gain (loss) from disposal of discontinued operation, before income tax   200,000    
MiamiFlorida [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Discontinued operation, gain (loss) from disposal of discontinued operation, before income tax   400,000    
Newport Natural Health [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Discontinued operation, gain (loss) from disposal of discontinued operation, before income tax   100,000    
Asset-Based Revolving Credit Facility [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Carrying value of notes       $ 30,000,000
Senior Secured Debt [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Carrying value of notes       $ 255,000,000
Debt instrument, interest rate, stated percentage 6.75%     6.75%
Debt related commitment fees and debt issuance costs $ 700,000 900,000    
Production Costs [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Marketing and advertising expense $ 7,900,000 $ 9,200,000    
Notes [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Debt instrument term 7 years      
Debt instrument, maturity date Jun. 01, 2024      
Dallas TX [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Percentage of total revenue 22.10% 20.40%    
Los Angeles CA [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Percentage of total revenue 14.10% 15.00%    
Standby Letters of Credit [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Line of credit facility, maximum borrowing capacity       $ 5,000,000
Swing Line Loans [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Line of credit facility, maximum borrowing capacity       $ 7,500,000