Nature of Business - Additional Information (Detail)			3 Months Ended	12 Months Ended
	May 28, 2020	Apr. 16, 2020	Jun. 30, 2020	Dec. 31, 2020 Segment Station Location Market Installment
Segment Reporting Information [Line Items]
Number of reportable segments | Segment				3
Percentage of defer the employer portion of social security payroll tax of CARES act				6.20%
Number of installments of deferred employer portion of social security payroll tax of CARES act | Installment				2
Percentage of installment of deferred employer portion of social security payroll tax of CARES act				50.00%
Percentage of reduction in dividends			50.00%
Non-Employee Director
Segment Reporting Information [Line Items]
Percentage of decreased in annual fees	20.00%
Minimum
Segment Reporting Information [Line Items]
Percentage of reduction in salaries		2.50%
Maximum [Member]
Segment Reporting Information [Line Items]
Percentage of reduction in salaries		22.50%
Television
Segment Reporting Information [Line Items]
Number of stations owned				54
Radio
Segment Reporting Information [Line Items]
Number of stations owned				48
Radio operations stations, number of location | Location				16
Advertisements and Syndicate Radio Programming | Minimum
Segment Reporting Information [Line Items]
Number of markets owned | Market				100