Employee Stock Purchase Plan, Purchase Discount, Percent

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- Definition

Employee Stock Purchase Plan, Shares Authorized for Purchase

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- Definition

Employee Stock Purchase Plan, Shares Reserved for Future Issuance

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Exercise Price, Required Percentage of Fair Market Value

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- Definition

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

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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- Definition

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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.

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No definition available.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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SHARE-BASED COMPENSATION (Details) - USD ($)	12 Months Ended
SHARE-BASED COMPENSATION (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	May 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options available for issue	1,900,000
Exercise price required percentage of fair market value	100.00%
Award vesting period	4 years
Intrinsic value of options exercised	$ 18,800,000	$ 300,000	$ 300,000
Cash received from exercise of stock options	9,700,000	400,000	200,000
Fair value of options vested	8,200,000	10,600,000	8,600,000
Capitalized costs	0	0	0
Tax benefit from compensation expense	0	$ 0	$ 0
Compensation cost not yet recognized	$ 17,100,000
Compensation cost not yet recognized, period for recognition	1 year 2 months 12 days
Stock Option Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option contractual terms	7 years
2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Stock Purchase Plan, Shares Authorized for Purchase	$ 25,000
Employee Stock Purchase Plan, Purchase Discount, Percent	85.00%
Employee Stock Purchase Plan, Shares Reserved for Future Issuance				300,000
Issuance of common stock from ESPP (in shares)	142,640
2013 Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option contractual terms	7 years
2013 Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option contractual terms	10 years