Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Revenue.
Revenue from Contract with Customer, Including Assessed Tax	$ 24,967	$ 22,301
Revenue, Remaining Performance Obligation, Optional Exemption, Performance Obligation [true false]	true
Broadcast Advertising Revenue, Net [Member]
Revenue.
Revenue from Contract with Customer, Including Assessed Tax	$ 21,587	20,007
Digital Advertising Revenue [Member]
Revenue.
Revenue from Contract with Customer, Including Assessed Tax	1,749	1,000
Other Revenue [Member]
Revenue.
Revenue from Contract with Customer, Including Assessed Tax	$ 1,631	$ 1,294