The Company and Significant Accounting Policies - Additional Information (Detail)				3 Months Ended				6 Months Ended		12 Months Ended	48 Months Ended
	Jun. 04, 2021 USD ($)	Mar. 30, 2020 USD ($)	Nov. 30, 2017 USD ($)	Jun. 30, 2021 USD ($) Location shares	Mar. 31, 2021 USD ($)	Jun. 30, 2020 USD ($) shares	Mar. 31, 2020 USD ($)	Jun. 30, 2021 USD ($) Installment Segment Station Agreement Market Location shares	Jun. 30, 2020 USD ($) shares	Dec. 31, 2020 USD ($)	Jun. 30, 2021 USD ($) Location $ / shares shares	Aug. 27, 2019 USD ($)	Apr. 11, 2018 USD ($)	Jul. 13, 2017 USD ($)
Accounting Policies [Line Items]
Number of reportable segments | Segment								3
Percentage of reduction in dividends						50.00%
Percentage of defer the employer portion of social security payroll tax of CARES act								6.20%
Number of installments of deferred employer portion of social security payroll tax of CARES act | Installment								2
Percentage of installment of deferred employer portion of social security payroll tax of CARES act								50.00%
Restricted cash				$ 749,000				$ 749,000		$ 749,000	$ 749,000
Retransmission consent revenue				$ 9,300,000		$ 9,400,000		$ 18,900,000	$ 18,900,000
Number of Class A common stock shares converted | shares								1
Shares of dilutive securities not included in computation of diluted earnings per share | shares				684		519,690		342	602,774
Impairment charge related to indefinite life intangible assets								$ 1,326,000
Impairment charges related to intangible subject to amortization										5,300,000
Impairment charges related to property and equipment										1,500,000
Impairment charge				$ 112,000				1,438,000	$ 39,835,000
Amount approved under share purchase												$ 45,000,000.0	$ 30,000,000.0	$ 15,000,000.0
Aggregate purchase price of repurchased shares							$ 525,000
Unamortized debt issuance costs				2,138,000				2,138,000		1,796,000	2,138,000
Interest income related to available-for-sale securities				83,000		$ 539,000		223,000	1,162,000
Assets held for sale				7,248,000				7,248,000		2,141,000	7,248,000
Carrying value of assets				$ 778,018,000				$ 778,018,000		747,345,000	$ 778,018,000
Accounting Standards Update [Extensible List]								us-gaap:AccountingStandardsUpdate201912Member
Change in Accounting Principle, Accounting Standards Update, Adoption Date				Jan. 01, 2021				Jan. 01, 2021			Jan. 01, 2021
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]				true				true			true
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false]				true				true			true
Huston, Texas
Accounting Policies [Line Items]
Agreement amount to sell building		$ 5,400,000
Assets held for sale				$ 200,000				$ 200,000			$ 200,000
Laredo, Texas
Accounting Policies [Line Items]
Agreement amount to sell building							$ 2,900,000
Assets held for sale				2,000,000.0				2,000,000.0			2,000,000.0
Orlando, Florida
Accounting Policies [Line Items]
Impairment charge					$ 1,300,000
Assets held for sale				4,000,000.0				4,000,000.0			4,000,000.0
Consideration from sale of radio station					4,000,000.0
Carrying value of assets				4,000,000.0				4,000,000.0			4,000,000.0
Tampa, Florida Area
Accounting Policies [Line Items]
Impairment charge				100,000
Assets held for sale				1,100,000				1,100,000			1,100,000
Consideration from sale of radio station					$ 1,100,000
Carrying value of assets				1,200,000				1,200,000			1,200,000
Available-for-Sale Securities
Accounting Policies [Line Items]
Interest income related to available-for-sale securities				100,000				$ 200,000
2017 Credit Facility
Accounting Policies [Line Items]
Agreement date			Nov. 30, 2017
Additional borrowing capacity			$ 100,000,000.0
First lien net leverage ratio			4.00%
Certain customary events of default, number of business days to default in the payment of interest on borrowings								3 days
Certain customary events of default, number of days default continue for compliance with other agreement								30 days
Certain customary events of default, number of days default continue for financial statement delivery obligations								10 days
Certain customary events of default, indebtedness aggregate amount								$ 15,000,000.0
Certain customary events of default, failure in payment of final judgments aggregate amount								$ 15,000,000.0
Certain customary events of default, failure in payment of final judgments aggregate amount period								30 days
Percentage of fee equal to amount of outstanding loans	0.375%
Fee amount	$ 600,000
2017 Credit Facility | Eurodollar Rate
Accounting Policies [Line Items]
Variable interest rate basis spread on debt			2.75%
2017 Credit Facility | Base Rate Margin
Accounting Policies [Line Items]
Variable interest rate basis spread on debt			1.75%
2017 Credit Facility | Term Loan B Facility
Accounting Policies [Line Items]
Senior Secured debt			$ 300,000,000.0
Maturity date of revolving credit facility			Nov. 30, 2024
2013 Credit Facility | Term Loan B Facility
Accounting Policies [Line Items]
Carrying value of term loan				211,600,000				$ 211,600,000			211,600,000
Unamortized debt issuance costs				2,100,000				2,100,000			2,100,000
Estimated fair value of term loan				$ 211,900,000				$ 211,900,000			$ 211,900,000
Class A common stock
Accounting Policies [Line Items]
Amount approved under share purchase												$ 15,000,000.0	$ 15,000,000.0
Number of shares repurchased | shares				0				0			8,600,000
Aggregate purchase price of repurchased shares											$ 32,200,000
Average price of repurchased shares | $ / shares											$ 3.76
Stock Options And Restricted Stock Units
Accounting Policies [Line Items]
Share-based compensation expenses				$ 1,100,000		800,000		$ 2,200,000	1,600,000
Employee Stock Options
Accounting Policies [Line Items]
Share-based compensation expenses				0		0		0	0
Restricted Stock Units
Accounting Policies [Line Items]
Total unrecognized compensation expense related to grants of restricted stock units				4,000,000.0				$ 4,000,000.0			$ 4,000,000.0
Weighted average period for unrecognized compensation expense related to grants of restricted stock units								1 year 4 months 24 days
Univision
Accounting Policies [Line Items]
Payment of sales representation fees to television stations				2,000,000.0		1,400,000		$ 3,900,000	3,600,000
Number of marketing and sales agreements | Agreement								2
Number of markets involved in sales and marketing | Market								6
Amount due from television stations for carriage				6,300,000				$ 6,300,000			$ 6,300,000
Retransmission consent revenue				$ 6,500,000		$ 6,800,000		$ 13,300,000	$ 13,800,000
Common stock percentage held by Univision				11.00%				11.00%			11.00%
UniMas
Accounting Policies [Line Items]
Affiliate advertising minutes per hour for which entity has right to sell								4 minutes 30 seconds
Accounting Standards Update 2016-18
Accounting Policies [Line Items]
Restricted cash				$ 700,000				$ 700,000		700,000	$ 700,000
Minimum | Employee Stock Options
Accounting Policies [Line Items]
Vesting period								1 year
Minimum | Restricted Stock Units
Accounting Policies [Line Items]
Vesting period								1 year
Minimum | Univision
Accounting Policies [Line Items]
Affiliate advertising minutes per hour for which entity has right to sell								4 minutes
Maximum | Employee Stock Options
Accounting Policies [Line Items]
Vesting period								4 years
Maximum | Restricted Stock Units
Accounting Policies [Line Items]
Vesting period								4 years
Television
Accounting Policies [Line Items]
Number of stations owned | Station								54
Carrying value of assets				$ 436,149,000				$ 436,149,000		425,899,000	$ 436,149,000
Television | FCC Licenses
Accounting Policies [Line Items]
Impairment charge related to indefinite life intangible assets										23,500,000
Radio
Accounting Policies [Line Items]
Number of stations owned | Station								48
Radio operations stations, number of location | Location				16				16			16
Impairment charge related to indefinite life intangible assets								$ 1,326,000
Carrying value of assets				$ 123,066,000				$ 123,066,000		125,426,000	$ 123,066,000
Radio | FCC Licenses
Accounting Policies [Line Items]
Impairment charge related to indefinite life intangible assets										9,000,000.0
Advertisements and Syndicate Radio Programming | Minimum
Accounting Policies [Line Items]
Number of markets owned | Market								100
Digital
Accounting Policies [Line Items]
Impairment of goodwill										800,000
Carrying value of assets				$ 218,803,000				$ 218,803,000		$ 196,020,000	$ 218,803,000