Goodwill and Other Intangible Assets - Composition of Company's Acquired Intangible Assets and Associated Accumulated Amortization (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Schedule Of Intangible Assets [Line Items]
Gross Carrying Amount	$ 94,890	$ 91,490
Accumulated Amortization	74,697	71,678
Net Carrying Amount	20,193	19,812
Intangible assets not subject to amortization:
Total intangible assets	240,894	240,513
FCC
Intangible assets not subject to amortization:
Licenses	220,701	220,701
Television network affiliation agreements
Schedule Of Intangible Assets [Line Items]
Weighted average remaining life in years	7 years
Gross Carrying Amount	65,089	65,089
Accumulated Amortization	48,851	46,530
Net Carrying Amount	16,238	18,559
Customer base
Schedule Of Intangible Assets [Line Items]
Weighted average remaining life in years	3 years
Gross Carrying Amount	3,146	746
Accumulated Amortization	935	473
Net Carrying Amount	2,211	273
Other
Schedule Of Intangible Assets [Line Items]
Weighted average remaining life in years	11 years
Gross Carrying Amount	26,655	25,655
Accumulated Amortization	24,911	24,675
Net Carrying Amount	$ 1,744	$ 980