STOCK-BASED COMPENSATION - NARRATIVE (Details)	3 Months Ended
Mar. 31, 2020 USD ($) 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
Unrecognized compensation cost \| $	$ 9,600,000
Unrecognized compensation cost, recognized over an estimated weighted-average period	2 years 7 months 2 days
Stock options outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based payment award vesting period	4 years
Stock options outstanding \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based payment award expiration period	7 years
Stock options outstanding \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based payment award expiration period	10 years
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
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
Employee stock purchase plan 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)	10,162
Shares available for purchase (in shares)	243,275

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

No definition available.

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

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

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

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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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- Definition

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

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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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