Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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SHARE-BASED COMPENSATION - Other Award Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Significant ranges of outstanding and exercisable options [Line Items]
Number of options outstanding	823,347		823,347		883,347
Weighted average remaining contractual life options outstanding			1 year 9 months 18 days
Weighted average exercise price options outstanding	$ 8.75		$ 8.75		$ 8.38
Number of options exercisable	823,347		823,347
Weighted average exercise price options exercisable	$ 8.75		$ 8.75
Recognized Non-Cash Compensation Expense [Line Items]
Total Non cash compensation expense recognized	$ 2,951	$ 982	$ 6,055	$ 2,067
Exercise prices from 1.34 to 1.34
Significant ranges of outstanding and exercisable options [Line Items]
Number of options outstanding	251,937		251,937
Weighted average remaining contractual life options outstanding			7 months 6 days
Weighted average exercise price options outstanding	$ 1.34		$ 1.34
Number of options exercisable	251,937		251,937
Weighted average exercise price options exercisable	$ 1.34		$ 1.34
Exercise prices from 2.02 to 13.98
Significant ranges of outstanding and exercisable options [Line Items]
Number of options outstanding	571,410		571,410
Weighted average remaining contractual life options outstanding			2 years 3 months 18 days
Weighted average exercise price options outstanding	$ 12.02		$ 12.02
Number of options exercisable	571,410		571,410
Weighted average exercise price options exercisable	$ 12.02		$ 12.02
Station operating expenses [Member]
Recognized Non-Cash Compensation Expense [Line Items]
Total Non cash compensation expense recognized	$ 1,680	372	$ 3,643	577
Corporate general and administrative expenses [Member]
Recognized Non-Cash Compensation Expense [Line Items]
Total Non cash compensation expense recognized	2,050	1,105	4,010	2,494
Stock-based compensation expense included in operating expenses [Member]
Recognized Non-Cash Compensation Expense [Line Items]
Total Non cash compensation expense recognized	3,730	1,477	7,653	3,071
Income tax benefit (net of a fully reserved valuation allowance for prior year) [Member]
Recognized Non-Cash Compensation Expense [Line Items]
Total Non cash compensation expense recognized	$ 779	$ 495	$ 1,598	$ 1,004