Adjustment To Additional Paid In Capital, Reincorporation

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Amount per share of equity securities issued under the employee stock purchase plan.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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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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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SHAREHOLDERS' EQUITY - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	May 31, 2004	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Aug. 14, 2018	Dec. 31, 2015
Stock-based compensation
Par value (in dollars per share)					$ 0.0001
Options exercised during period (in shares)		278,000	1,000,892
Net proceeds from options exercised during the period		$ 1,500	$ 7,000
ESPP
Stock-based compensation
Number of shares authorized for issuance (in shares)		3,000,000
Number of shares available for future issuance (in shares)		302,549
Shares sold (in shares)		106,500	261,569
Weighted average purchase price of shares sold (in dollars per share)		$ 4.95	$ 7.49
Proceeds from shares sold		$ 500	$ 2,000
ESPP \| Minimum
Stock-based compensation
Purchase price expressed as percentage of fair market value of common stock	85.00%
Common Stock
Stock-based compensation
Reclassification due to reincorporation						$ (264,505)
Shares sold (in shares)		107,000	261,569	201,264
Options exercised during period (in shares)		278,000	1,001,142	715,655
Additional Paid-In Capital
Stock-based compensation
Reclassification due to reincorporation						$ 264,505