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

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Aggregate number of common shares reserved for future issuance.

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Number of additional shares authorized for issuance under share-based payment arrangement.

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Number of shares authorized for issuance under share-based payment arrangement.

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

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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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Purchase price of common stock expressed as a percentage of its fair value.

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

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SHARE-BASED COMPENSATION, STOCK OPTIONS, AND RESTRICTED SECURITIES (Details) - USD ($) $ in Thousands		1 Months Ended		12 Months Ended		43 Months Ended
	Jan. 01, 2019	Mar. 31, 2019	Mar. 31, 2015	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2018	Feb. 28, 2019
Stock options
Aggregate number of shares reserved for issuance				282,213
Stock-based compensation (in dollars)				$ 268	$ 618
Stock Options
Stock options
Granted (in shares)				3,000	520
Expected term				10 years
Aggregate number of shares reserved for issuance				4,187
Stock-based compensation (in dollars)				$ 165	$ 528
2010 Plan
Stock options
Granted (in shares)						0
Expected term				10 years
2015 Plan
Stock options
Shares available for future grants				68
Shares authorized for issuance		32,000					5,333
Expected term				10 years
Increased share reserve		26,667
2007 Plan
Stock options
Expected term				10 years
Employee Stock Purchase Plan
Stock options
Shares authorized for issuance			250
Percentage of outstanding shares reserved for future issuance			1.00%
Increase in shares of common stock reserved for issuance (in shares)			67
Aggregate number of shares reserved for issuance				264
Stock issued under ESPP (in shares)	36
Offering Period				6 months
Stock-based compensation (in dollars)					$ 2
Employee Stock Purchase Plan \| Maximum
Stock options
Aggregate number of shares reserved for issuance			1,667
Common Stock
Stock options
Stock issued under ESPP (in shares)				36	48