v3.8.0.1

SHARE-BASED COMPENSATION - Other Award Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Significant ranges of outstanding and exercisable options [Line Items]
Number of options outstanding	883,347	329,562
Weighted average remaining contractual life options outstanding	2 years 2 months 12 days
Weighted average exercise price options outstanding	$ 8.38	$ 1.91
Number of options exercisable	883,347
Weighted average exercise price options exercisable	$ 8.38
Recognized Non-Cash Compensation Expense [Line Items]
Total Non cash compensation expense recognized	$ 6,239	$ 4,218	$ 3,488
The amount of the Company's windfall tax benefit account	$ 4,174	3,145
Exercise prices from 1.34 to 1.34
Significant ranges of outstanding and exercisable options [Line Items]
Number of options outstanding	300,437
Weighted average remaining contractual life options outstanding	1 year 1 month 6 days
Weighted average exercise price options outstanding	$ 1.34
Number of options exercisable	300,437
Weighted average exercise price options exercisable	$ 1.34
Exercise prices from 2.02 to 11.78
Significant ranges of outstanding and exercisable options [Line Items]
Number of options outstanding	582,910
Weighted average remaining contractual life options outstanding	2 years 9 months 18 days
Weighted average exercise price options outstanding	$ 12.02
Number of options exercisable	582,910
Weighted average exercise price options exercisable	$ 12.02
Station operating expenses [Member]
Recognized Non-Cash Compensation Expense [Line Items]
Total Non cash compensation expense recognized	$ 1,694	1,363	1,259
Corporate general and administrative expenses [Member]
Recognized Non-Cash Compensation Expense [Line Items]
Total Non cash compensation expense recognized	7,873	5,176	4,265
Stock-based compensation expense included in operating expenses [Member]
Recognized Non-Cash Compensation Expense [Line Items]
Total Non cash compensation expense recognized	9,567	6,539	5,524
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	$ 3,328	$ 2,321	$ 2,036

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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

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

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The number of exercisable share options (fully vested and expected to vest) that may be converted as of the balance sheet date.

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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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