Revenues - Summary of Disaggregation of Broadcast Advertising Revenue by Sales Channel (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Disaggregation Of Revenue [Line Items]
Total revenue	$ 221,695	$ 178,410	$ 418,867	$ 327,290
Advertising
Disaggregation Of Revenue [Line Items]
Total revenue	35,347	36,438	66,804	70,113
Advertising | Local Direct
Disaggregation Of Revenue [Line Items]
Total revenue	6,009	5,729	11,430	10,969
Advertising | Local Agency
Disaggregation Of Revenue [Line Items]
Total revenue	13,017	15,219	25,570	28,407
Advertising | National Agency
Disaggregation Of Revenue [Line Items]
Total revenue	$ 16,321	$ 15,490	$ 29,804	$ 30,737