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

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Percentage of vesting of award 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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SHARE-BASED COMPENSATION - Additional Information (Details) shares in Millions	1 Months Ended		3 Months Ended		6 Months Ended
	Mar. 31, 2022 shares	Jun. 30, 2018 installment shares	Jun. 30, 2024 USD ($) shares	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($) shares	Jun. 30, 2023 USD ($)	Dec. 31, 2020 shares
SHARE-BASED COMPENSATION
Share-based compensation expenses			$ 1,563,000	$ 2,033,000	$ 2,901,000	$ 3,838,000
Stock options
SHARE-BASED COMPENSATION
Share-based compensation expenses			100,000	100,000	100,000	300,000
Unrecognized compensation cost related to non-vested stock options			0		0
Restricted Stock Units and PRSUs
SHARE-BASED COMPENSATION
Share-based compensation expenses			1,500,000	$ 1,900,000	$ 2,800,000	$ 3,600,000
Non-vested awards not yet recognized weighted-average period for recognition					2 years
Unrecognized compensation cost related to non-vested restricted stock			$ 8,800,000		$ 8,800,000
Fair value of restricted stock vested					$ 4,000,000.0
2018 Plan
SHARE-BASED COMPENSATION
Annual percentage increase in number of shares authorized for issuance		4.00%
Vesting terms of stock options		stock options vest 25% upon the first anniversary of the date of grant and the remainder ratably monthly thereafter for 36 months. Restricted stock units generally vest ratably in three equal installments on the first, second and third anniversaries of the grant date.
Number of vesting installments \| installment		3
Shares available for future issuance \| shares			0.7		0.7
2018 Plan \| PRSUs \| Common Stock
SHARE-BASED COMPENSATION
Weighted average price, number of days trailing		30 days
2018 Plan \| First Anniversary of Date of Grant
SHARE-BASED COMPENSATION
Vesting percentage of stock options		25.00%
2018 Plan \| Maximum
SHARE-BASED COMPENSATION
Number of shares authorized for issuance \| shares		1.4
Maximum contractual term of stock options		10 years
2020 Plan
SHARE-BASED COMPENSATION
Number of additional shares authorized for issuance \| shares	0.5
Shares available for future issuance \| shares			0.1		0.1
2020 Plan \| Maximum
SHARE-BASED COMPENSATION
Number of shares authorized for issuance \| shares							0.4