Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Cash received on stock transaction after deduction of issuance costs.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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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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Gross number of share options (or share units) granted during the period.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Percentage of vesting of share-based compensation awards.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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SUBSEQUENT EVENTS (Details) - USD ($) $ / shares in Units, $ in Thousands			2 Months Ended	12 Months Ended
	Feb. 20, 2020	Jan. 23, 2020	Mar. 13, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Subsequent Event [Line Items]
Stock options granted in period (in shares)				296,450	442,956	738,893
Exercise price (in USD per share)				$ 2.27	$ 2.15	$ 0.00
Shares issued (in shares)				100,735,889	91,445,066	74,366,824	66,205,153
Employee Stock Option
Subsequent Event [Line Items]
Stock options granted in period (in shares)				300,000	420,000	740,000
Award vesting period				2 years
Employee Stock Option \| Subsequent Event
Subsequent Event [Line Items]
Stock options granted in period (in shares)		570,000
Exercise price (in USD per share)		$ 1.76
Award vesting period		5 years
Employee Stock Option \| Share-based Compensation Award, Tranche One \| Subsequent Event
Subsequent Event [Line Items]
Award vesting rights, percentage		50.00%
Employee Stock Option \| Share-based Compensation Award, Tranche Two \| Subsequent Event
Subsequent Event [Line Items]
Award vesting rights, percentage		25.00%
Employee Stock Option \| Share-based Compensation Award, Tranche Three \| Subsequent Event
Subsequent Event [Line Items]
Award vesting rights, percentage		25.00%
Restricted Stock Units (RSUs)
Subsequent Event [Line Items]
Shares granted in share-based compensation awards (in shares)				730,000	1,190,000	1,390,000
Award vesting period				3 years
Restricted Stock Units (RSUs) \| Subsequent Event
Subsequent Event [Line Items]
Shares granted in share-based compensation awards (in shares)		740,000
Restricted Stock Units (RSUs) \| Share-based Compensation Award, Tranche Four \| Subsequent Event
Subsequent Event [Line Items]
Award vesting rights, percentage		50.00%
Restricted Stock Units (RSUs) \| Share-based Compensation Award, Tranche Five \| Subsequent Event
Subsequent Event [Line Items]
Award vesting rights, percentage		25.00%
Restricted Stock Units (RSUs) \| Share-based Compensation Award, Tranche Six \| Subsequent Event
Subsequent Event [Line Items]
Award vesting rights, percentage		25.00%
At The Market Sale Of Stock
Subsequent Event [Line Items]
Sale of stock consideration received				$ 19,680	$ 31,520	$ 14,150
At The Market Sale Of Stock \| Subsequent Event
Subsequent Event [Line Items]
Shares issued (in shares)			2,390,000
Sale of Stock, Price Per Share			$ 1.69
Sale of stock consideration received			$ 3,960
Public Offering \| Subsequent Event
Subsequent Event [Line Items]
Shares issued (in shares)	11,300,000
Sale of Stock, Price Per Share	$ 1.47
Sale of stock consideration received	$ 15,070