Property and Equipment - Property and Equipment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment excluding land gross	$ 238,400	$ 254,600
Less accumulated depreciation	183,930	191,183
Property and equipment excluding land, net	54,500	63,400
Land	8,000	8,600
Property and equipment, total	62,498	72,004
Buildings
Property, Plant and Equipment [Line Items]
Property and equipment excluding land gross	$ 18,600	19,700
Property and equipment, Estimated useful life	40 years
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment excluding land gross	$ 1,200	1,900
Transmission, studio and other broadcast equipment
Property, Plant and Equipment [Line Items]
Property and equipment excluding land gross	$ 158,400	170,300
Transmission, studio and other broadcast equipment | Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, Estimated useful life	5 years
Transmission, studio and other broadcast equipment | Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, Estimated useful life	15 years
Office and computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment excluding land gross	$ 33,600	33,900
Office and computer equipment | Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, Estimated useful life	3 years
Office and computer equipment | Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, Estimated useful life	7 years
Transportation equipment
Property, Plant and Equipment [Line Items]
Property and equipment excluding land gross	$ 5,400	6,800
Property and equipment, Estimated useful life	5 years
Leasehold improvements and land improvements
Property, Plant and Equipment [Line Items]
Property and equipment excluding land gross	$ 21,200	$ 22,000
Property and equipment, Estimated useful life	Lesser of lease life or useful life