STOCK-BASED COMPENSATION - Narrative (Details) - USD ($) $ in Thousands		12 Months Ended
Oct. 01, 2018	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Automatic increase in shares authorized based on percent of total shares outstanding on December 31st of the preceding calendar year.		4.00%
Outstanding, intrinsic value		$ 1,716
Exercisable intrinsic value		640
Unrecognized compensation cost		$ 885
Unrecognized compensation, weighted average amortization period		2 years 5 months 26 days
2018 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized (in shares)		621,022
Stock awards, contractual life (up to)	10 years

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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Amount of cost to be recognized for option under share-based payment arrangement.

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

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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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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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Share-based Payment Award, Number of Additional Shares Authorized, Based on Percent of Total Shares Outstanding End of Prior Year, Percent

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