v3.10.0.1

SHARE-BASED COMPENSATION - Other Award Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Significant ranges of outstanding and exercisable options [Line Items]
Number of options outstanding	755,210	883,347
Weighted average remaining contractual life options outstanding	1 year 4 months 24 days
Weighted average exercise price options outstanding	$ 9.42	$ 8.38
Number of options exercisable	755,210
Weighted average exercise price options exercisable	$ 9.42
Recognized Non-Cash Compensation Expense [Line Items]
Total Non cash compensation expense recognized	$ 11,989	$ 6,239	$ 4,218
The amount of the Company's windfall tax benefit account	$ 3,382	4,174
Exercise prices from 1.34 to 1.34
Significant ranges of outstanding and exercisable options [Line Items]
Number of options outstanding	184,800
Weighted average remaining contractual life options outstanding	1 month 6 days
Weighted average exercise price options outstanding	$ 1.34
Number of options exercisable	184,800
Weighted average exercise price options exercisable	$ 1.34
Exercise prices from 4.76 to 13.98
Significant ranges of outstanding and exercisable options [Line Items]
Number of options outstanding	570,410
Weighted average remaining contractual life options outstanding	1 year 9 months 18 days
Weighted average exercise price options outstanding	$ 12.04
Number of options exercisable	570,410
Weighted average exercise price options exercisable	$ 12.04
Station operating expenses [Member]
Recognized Non-Cash Compensation Expense [Line Items]
Total Non cash compensation expense recognized	$ 6,855	1,694	1,363
Corporate general and administrative expenses [Member]
Recognized Non-Cash Compensation Expense [Line Items]
Total Non cash compensation expense recognized	8,294	7,873	5,176
Stock-based compensation expense included in operating expenses [Member]
Recognized Non-Cash Compensation Expense [Line Items]
Total Non cash compensation expense recognized	15,149	9,567	6,539
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	$ 3,160	$ 3,328	$ 2,321

X

- 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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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 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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