Goodwill and Other Intangible Assets - Carrying Amount of Goodwill (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Line Items]
Goodwill	$ 50,081,000	$ 50,081,000	$ 50,081,000
Television
Goodwill [Line Items]
Goodwill	35,912,000	35,912,000	35,912,000
Impairment	0	0	0
Radio
Goodwill [Line Items]
Impairment			(700,000)
Digital
Goodwill [Line Items]
Goodwill	14,169,000	14,169,000	$ 14,169,000
Impairment	$ 0	$ 0