STOCK-BASED COMPENSATION - NARRATIVE (Details)	3 Months Ended	6 Months Ended
Dec. 31, 2020 shares	Jun. 30, 2021 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
Restricted stock outstanding (in shares)	802,000
Shares available for purchase (in shares)		215,338
Unrecognized compensation cost \| $		$ 4,100,000
Unrecognized compensation cost, recognized over an estimated weighted-average period		1 year 9 months 18 days
Stock options outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based payment award vesting period		4 years
Stock-based payment award expiration period		7 years
RSAs outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based payment award vesting period		1 year
Granted (in shares)		0
Restricted stock outstanding (in shares)	130,000	0
RSUs outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based payment award vesting period		3 years
Restricted stock outstanding (in shares)		364,000
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)		15,543
Market Performance Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	250,000

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

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

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Aggregate number of common shares reserved for future issuance.

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-Publisher FASB
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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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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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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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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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

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

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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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