Goodwill and Intangible Assets - Other (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2017
Changes in other amortizable intangible assets
Balance at the beginning of the period	$ 48,163	$ 61,499
Additions	92	94
Amortization	(13,280)	(13,430)	$ (13,500)
Net balance at the end of the period	34,975	48,163	61,499
Future estimated amortization expense
2018				$ 13,241
2019				8,486
2020				6,058
2021				5,752
2022 and thereafter				1,438
Total	$ 48,163	61,499	61,499	34,975
Weighted Average
Changes in other amortizable intangible assets
Remaining amortization period	3 years 4 months 24 days
Affiliate relationships
Changes in other amortizable intangible assets
Balance at the beginning of the period	$ 44,468	56,766
Amortization	(12,125)	(12,298)
Net balance at the end of the period	32,343	44,468	56,766
Future estimated amortization expense
Total	44,468	56,766	56,766	32,343
Advertiser relationships
Changes in other amortizable intangible assets
Balance at the beginning of the period	1,792	2,344
Amortization	(552)	(552)
Net balance at the end of the period	1,240	1,792	2,344
Future estimated amortization expense
Total	1,792	2,344	2,344	1,240
Non-compete agreement
Changes in other amortizable intangible assets
Balance at the beginning of the period	1,784	2,333
Amortization	(549)	(549)
Net balance at the end of the period	1,235	1,784	2,333
Future estimated amortization expense
Total	1,784	2,333	2,333	1,235
Other intangibles
Changes in other amortizable intangible assets
Balance at the beginning of the period	119	56
Additions	92	94
Amortization	(54)	(31)
Net balance at the end of the period	157	119	56
Future estimated amortization expense
Total	$ 119	$ 56	$ 56	$ 157