The reduction in number of available shares when a share is issued under the share based compensation.

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- Definition

The estimated dividend rate (a percentage of the share price) used in option-pricing model.

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- Definition

The offering period of the employee stock purchase plan ("ESPP").

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Average Purchase Price

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Amount

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Shares Available For Purchase

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- Definition

Aggregate number of common shares reserved for future issuance.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
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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

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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- 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 highest quantity of shares an employee can purchase under the plan per period.

+ References

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- Definition

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

+ References

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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-Publisher FASB
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- Definition

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

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- Definition

Number of shares purchased for issuance 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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- Definition

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

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No definition available.

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STOCK-BASED COMPENSATION - Narrative (Details)		12 Months Ended
STOCK-BASED COMPENSATION - Narrative (Details)	Jun. 14, 2019 shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of available shares consumed for each restricted stock and restricted stock units issued		1.75
Expected dividend yield		0.00%
Unrecognized compensation cost \| $		$ 8,000,000
Unrecognized compensation cost, recognized over an estimated weighted-average period		2 years 7 months 2 days
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based payment award vesting period		4 years
Increase in number of common shares reserved for issuance (in shares)	2,595,751
Stock options outstanding (in shares)		967,000
Stock options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based payment award expiration period		7 years
Stock options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based payment award expiration period		10 years
Time-based stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share) \| $ / shares		$ 3.69
Stock options outstanding (in shares)		967,000	1,862,000
RSAs outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based payment award vesting period		1 year
RSUs outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based payment award vesting period		3 years
Market condition based stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding (in shares)		0	272,081
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of fair market value on the purchase date		85.00%
Maximum number of shares per employee (in shares)		2,000
Offering period		6 months
Maximum value of shares per employee \| $		$ 25,000
Common stock reserved for issuance (in shares)		1,000,000.0
Purchases under ESPP (in shares)		21,741
Average purchase price (in dollars per share) \| $ / shares		$ 7.60
Shares available for purchase (in shares)		253,437