The Company and Significant Accounting Policies - Additional Information (Detail)			3 Months Ended			12 Months Ended	33 Months Ended
	Mar. 30, 2020 USD ($)	Nov. 30, 2017 USD ($)	Mar. 31, 2020 USD ($) Segment Station Location Market Agreement $ / shares shares	Sep. 30, 2019 USD ($) Station	Mar. 31, 2019 USD ($) shares	Dec. 31, 2019 USD ($)	Mar. 31, 2020 USD ($) Location $ / shares shares	Jan. 22, 2020 USD ($)	Aug. 27, 2019 USD ($)	Apr. 11, 2018 USD ($)	Jul. 13, 2017 USD ($)
Accounting Policies [Line Items]
Number of reportable segments | Segment			3
Restricted cash			$ 734,000			$ 734,000	$ 734,000
Retransmission consent revenue			$ 9,600,000		$ 8,800,000
Number of Class A common stock shares converted | shares			1
Shares of dilutive securities not included in computation of diluted earnings per share | shares			659,828		43,534
Impairment of goodwill			$ 800,000
Impairment charge related to indefinite life intangible assets			32,257,000
Goodwill			45,711,000			46,511,000	45,711,000
Amount approved under share purchase									$ 45,000,000	$ 30,000,000	$ 15,000,000
Aggregate purchase price of repurchased shares			525,000		$ 7,706,000
Unamortized debt issuance costs			2,120,000			2,226,000	2,120,000
Interest income related to available-for-sale securities			624,000		919,000
Agreement amount to sell building				$ 1,000,000
Assets held for sale			6,878,000			950,000	6,878,000
Huston, Texas
Accounting Policies [Line Items]
Agreement amount to sell building	$ 5,400,000
Assets held for sale	$ 200,000
Laredo, Texas
Accounting Policies [Line Items]
Agreement amount to sell building			2,900,000
Assets held for sale			$ 2,000,000				2,000,000
ION Media Stations, Inc. | KMCC-TV
Accounting Policies [Line Items]
Consideration from sale of television station								$ 4,000,000
Discontinued operation, description			On January 22, 2020, the Company entered into an agreement with ION Media Stations, Inc. to sell television station KMCC-TV, serving the Las Vegas area, for $4.0 million.
Assets held for sale								$ 3,800,000
Available-for-Sale Securities
Accounting Policies [Line Items]
Interest income related to available-for-sale securities			$ 600,000
2017 Credit Facility
Accounting Policies [Line Items]
Agreement date		Nov. 30, 2017
Additional borrowing capacity		$ 100,000,000
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
Certain customary events of default, failure in payment of final judgments aggregate amount			$ 15,000,000
Certain customary events of default, failure in payment of final judgments aggregate amount period			30 days
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
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			$ 215,400,000				215,400,000
Unamortized debt issuance costs			2,100,000				2,100,000
Estimated fair value of term loan			$ 179,400,000				$ 179,400,000
Class A common stock
Accounting Policies [Line Items]
Amount approved under share purchase									$ 15,000,000	$ 15,000,000
Number of shares repurchased | shares			300,000				8,600,000
Average price of repurchased shares | $ / shares			$ 2.02				$ 3.76
Aggregate purchase price of repurchased shares			$ 500,000				$ 32,200,000
Stock Options And Restricted Stock Units
Accounting Policies [Line Items]
Share-based compensation expenses			800,000		800,000
Employee Stock Options
Accounting Policies [Line Items]
Share-based compensation expenses			0
Restricted Stock Units
Accounting Policies [Line Items]
Total unrecognized compensation expense related to grants of restricted stock units			$ 3,100,000				3,100,000
Weighted average period for unrecognized compensation expense related to grants of restricted stock units			1 year 6 months
Univision
Accounting Policies [Line Items]
Payment of sales representation fees to television stations			$ 2,200,000		2,000,000
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			$ 6,800,000				$ 6,800,000
Retransmission consent revenue			$ 7,000,000		$ 6,700,000
Common stock percentage held by Univision			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
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			56
Impairment of goodwill			$ 0
Impairment charge related to indefinite life intangible assets			23,457,000
Goodwill			$ 40,549,000			40,549,000	$ 40,549,000
Percentage of fair value of assets			28.00%
Number of stations relocated | Station				2
Television | FCC Licenses
Accounting Policies [Line Items]
Impairment charge related to indefinite life intangible assets			$ 23,500,000			4,000,000
Radio
Accounting Policies [Line Items]
Number of stations owned | Station			49
Radio operations stations, number of location | Location			16				16
Impairment charge related to indefinite life intangible assets			$ 8,800,000
Goodwill			0				$ 0
Radio | FCC Licenses
Accounting Policies [Line Items]
Impairment charge related to indefinite life intangible assets			$ 8,800,000			200,000
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			27,700,000
Goodwill			5,162,000			$ 5,962,000	$ 5,162,000
Impairment charges related to intangible subject to amortization			5,300,000
Impairment charges related to property and equipment			$ 1,500,000