Broadcast Licenses, Goodwill and Other Intangible Assets (Details Textual) - USD ($)	3 Months Ended														12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	[1]	Dec. 31, 2016	[1]	Sep. 30, 2016	[1]	Jun. 30, 2016	[1]	Mar. 31, 2016	[1]	Dec. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Impairment of intangible assets	$ 1,449,000	$ 0	$ 0	$ 0		$ 0		$ 0		$ 0		$ 0		$ 874,000	$ 1,449,000	$ 0	$ 874,000
Amortization Expense															860,000	$ 642,000	$ 231,000
2018	1,094,000														1,094,000
2019	691,000														691,000
2020	475,000														475,000
2021	49,000														49,000
2022	$ 39,000														$ 39,000

[1] Certain prior year amounts and March 31, 2017 quarterly data have been reclassified to conform with current presentation.