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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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.

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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

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

Percentage of vesting of award under share-based payment arrangement.

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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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SHARE-BASED COMPENSATION - Narrative (Details) - USD ($) $ / shares in Units, shares in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding (in shares)		6,450		6,450		3,942
Share-based compensation expense		$ 229,000	$ 248,000	$ 911,000	$ 935,000
Unrecognized compensation expense		$ 3,500,000		$ 3,500,000
Weighted-average grant-date fair value of stock options granted (in dollars per share)				$ 0.69
Inducement awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding (in shares)		2,100		2,100
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		$ 200,000	200,000	$ 900,000	900,000
Weighted-average period				3 years 1 month 6 days
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense			$ (43,000)		$ 200,000
Unrecognized compensation expense		$ 0		$ 0
2014 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding (in shares)		4,300		4,300
Shares of common stock reserved for issuance (in shares)	7,900
Shares available for future issuance (in shares)		8,600		8,600
2014 Stock Incentive Plan \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				4 years
Period exercisable from date of grant				10 years
2014 Stock Incentive Plan \| Vesting on the First Anniversary of Date of Grant \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant vesting on the first anniversary percentage				25.00%
2014 Stock Incentive Plan \| Vesting at End of Each Successive Three-Month Period Thereafter \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant vesting on the first anniversary percentage				6.25%