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Revenue (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | [1] | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Revenues [Abstract] |  |  |  |  |  |  |  |  |  |  |
Revenue, Net, Total | $ 32,938 | $ 31,648 | $ 32,234 | $ 28,009 | $ 31,464 | $ 30,269 | $ 30,261 | $ 26,155 | $ 124,829 | $ 118,149 | $ 118,955
Broadcast Advertising Revenue, net [Member] |  |  |  |  |  |  |  |  |  |  |
Revenues [Abstract] |  |  |  |  |  |  |  |  |  |  |
Revenue, Net, Total |  |  |  |  |  |  |  |  | 114,929 | 109,175 | 110,053
Digital Advertising Revenue [Member] |  |  |  |  |  |  |  |  |  |  |
Revenues [Abstract] |  |  |  |  |  |  |  |  |  |  |
Revenue, Net, Total |  |  |  |  |  |  |  |  | 3,900 | 3,610 | 3,567
Other Revenue [Member] |  |  |  |  |  |  |  |  |  |  |
Revenues [Abstract] |  |  |  |  |  |  |  |  |  |  |
Revenue, Net, Total |  |  |  |  |  |  |  |  | $ 6,000 | $ 5,364 | $ 5,335
[1] | March 31, 2017 quarterly data have been reclassified to conform with current presentation.

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