Quarterly Results of Operations (Details) - USD ($) $ / shares in Units, shares in Thousands	3 Months Ended									12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Quarterly Results of Operations (Unaudited)
Net operating revenue	$ 29,151,000	$ 28,845,000	$ 28,046,000	$ 22,301,000	$ 28,753,000	$ 24,143,000	$ 16,866,000	$ 26,051,000		$ 108,343,000	$ 95,813,000	$ 123,072,000
Station operating expenses	21,615,000	21,690,000	21,017,000	18,923,000	21,119,000	19,616,000	18,652,000	22,199,000		83,245,000	81,586,000	92,692,000
Corporate G&A	2,570,000	2,538,000	2,494,000	2,438,000	2,651,000	2,838,000	3,070,000	3,015,000		10,040,000	11,574,000	11,460,000
Other operating expense (income), net	32,000	(2,000)	(80,000)	57,000	(13,000)	50,000	46,000	(1,330,000)		7,000	(1,247,000)	112,000
Impairment of broadcast licenses						1,392,000	3,757,000		$ 0		5,149,000
Operating income	4,934,000	4,619,000	4,615,000	883,000	4,996,000	247,000	(8,659,000)	2,167,000		15,051,000	(1,249,000)	18,808,000
Other (income) expenses:
Interest expense	66,000	73,000	72,000	73,000	75,000	75,000	82,000	108,000		284,000	340,000	735,000
Interest income	(2,000)	(4,000)	(4,000)	(6,000)	(7,000)	(8,000)	(25,000)	(108,000)		(16,000)	(148,000)	(610,000)
Other income	(52,000)	(279,000)	(31,000)	(272,000)	(20,000)			(213,000)		(634,000)	(233,000)	(16,000)
Income before income taxes	4,922,000	4,829,000	4,578,000	1,088,000	4,948,000	180,000	(8,716,000)	2,380,000		15,417,000	(1,208,000)	18,699,000
Income tax provision (benefit)	1,230,000	1,375,000	1,325,000	330,000	2,680,000	1,130,000	(3,805,000)	700,000		$ 4,260,000	$ 705,000	$ 5,420,000
Net income	$ 3,692,000	$ 3,454,000	$ 3,253,000	$ 758,000	$ 2,268,000	$ (950,000)	$ (4,911,000)	$ 1,680,000
Basic	$ 0.60	$ 0.58	$ 0.54	$ 0.13	$ 0.38	$ (0.16)	$ (0.82)	$ 0.28		$ 1.85	$ (0.32)	$ 2.23
Weighted average common shares	5,922	5,917	5,917	5,913	5,880	5,869	5,868	5,866		5,917	5,871	5,834
Diluted earnings per share	$ 0.60	$ 0.58	$ 0.54	$ 0.13	$ 0.38	$ (0.16)	$ (0.82)	$ 0.28		$ 1.85	$ (0.32)	$ 2.23
Weighted average common and common equivalent shares	5,922	5,917	5,917	5,913	5,880	5,869	5,868	5,866		5,917	5,871	5,834