Revenues - Summary of Revenues Disaggregated by Major Source (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Disaggregation Of Revenue [Line Items]
Total revenue	$ 64,249	$ 64,680
Broadcast Advertising
Disaggregation Of Revenue [Line Items]
Total revenue	38,728	34,708
Digital Advertising
Disaggregation Of Revenue [Line Items]
Total revenue	13,331	14,472
Spectrum Usage Rights
Disaggregation Of Revenue [Line Items]
Total revenue	1,356	5,084
Retransmission Consent
Disaggregation Of Revenue [Line Items]
Total revenue	9,580	8,760
Other
Disaggregation Of Revenue [Line Items]
Total revenue	$ 1,254	$ 1,656