Summary of Significant Accounting Policies (Narrative) (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2023 USD ($) item shares	Jun. 30, 2022 shares	Jun. 30, 2023 USD ($) item segment $ / shares shares	Jun. 30, 2022 USD ($) shares	Dec. 31, 2022 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of market serving | item	27		27
Number of FM radio stations | item			79
Number of AM radio stations			33
Number of metro signals			80
Antidilutive securities excluded from computation of earnings per share, amount | shares	0	0	0	0
Securities at fair value	$ 10,300,000		$ 10,300,000		$ 10,000,000
Amortization of debt issuance costs			$ 18,000	$ 6,000
Cash dividend paid | $ / shares			$ 0
Debt securities, held to maturity	10,300,000		$ 10,300,000		10,100,000
Allowance for doubtful accounts receivable	$ 476,000		$ 476,000		$ 519,000
Number of Radio Markets | item			27
Number of operating segments | segment			1
Number of reportable segments | segment			1