Minimum Closing Market Value of Common Stock For Vesting

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- Definition

Minimum Consecutive Trading Days Stock Market Price For Vesting

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No definition available.

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- Definition

Non Qualified Stock Options [Abstract]

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- Definition

Restricted Stock [Abstract]

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No definition available.

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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.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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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

Gross number of share options (or share units) granted during the period.

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No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

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

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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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Number of share options (or share units) exercised during the current period.

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COMPENSATION PLANS (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for issuance	3,000,000
Total compensation expense	$ 4.2	$ 3.6	$ 3.6
Total unrecognized compensation expense	$ 5.0
Restricted Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards, outstanding	1,953,305	3,163,903
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise in the period	95,004		0
Awards, outstanding	3,351,684	2,075,821
Non Qualified Stock Options [Abstract]
Options granted, weighted average fair value	$ 2.33	$ 1.38	$ 0.61
Options exercised, intrinsic value	$ 0.3	$ 0.3
2015 [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, earned	0
Restricted Stock [Abstract]
Granted in period, weighted average fair value	$ 13.84
Service Based Vesting [Member] \| Restricted Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, earned	1,112,256
Shares granted	277,911
Restricted Stock [Abstract]
Granted in period, weighted average fair value	$ 4.16	$ 2.27	$ 1.07
Shares canceled	305,002
Service Based Vesting [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	72.80%	71.50%	63.80%
Service Based Vesting [Member] \| Key Employees [Member] \| Restricted Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	187,296
Restricted Stock [Abstract]
Vesting period	2 years
Service Based Vesting [Member] \| Key Employees [Member] \| Stock Options [Member]
Restricted Stock [Abstract]
Vesting period	3 years
Non Qualified Stock Options [Abstract]
Options granted in the period	623,274
Grant term	10 years
Service Based Vesting [Member] \| Director [Member] \| Restricted Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	90,615
Restricted Stock [Abstract]
Vesting period	1 year
Service And Market Condition Based Vesting [Member] \| Restricted Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility		81.70%	86.20%
Shares, earned	71,251
Restricted Stock [Abstract]
Granted in period, weighted average fair value	$ 2.10	$ 0.91
Shares canceled	0
Service And Market Condition Based Vesting [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	75.00%	81.70%	86.20%
Service And Market Condition Based Vesting [Member] \| Key Employees [Member] \| Stock Options [Member]
Restricted Stock [Abstract]
Vesting period	3 years
Non Qualified Stock Options [Abstract]
Options granted in the period	934,911
Grant term	5 years
Closing market value of common stock for vesting	$ 5.85
Minimum consecutive trading days	20 days
Service And Market Condition Based Vesting [Member] \| 2017 [Member] \| Restricted Shares [Member]
Restricted Stock [Abstract]
Vesting period	3 years
Service And Market Condition Based Vesting [Member] \| 2016 [Member] \| Restricted Shares [Member]
Restricted Stock [Abstract]
Vesting period	4 years
Service And Performance Based Vesting [Member] \| Restricted Shares [Member]
Restricted Stock [Abstract]
Granted in period, weighted average fair value	$ 3.91
Service And Performance Based Vesting [Member] \| Key Employees [Member] \| Restricted Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	187,296
Restricted Stock [Abstract]
Vesting period	1 year
Shares canceled	187,296