OTHER INCOME - Summary of Other Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
OTHER INCOME
COVID-19 relief		$ 1,725		$ 2,836
Unrealized and realized gain (loss) on investments (Note 5)	$ 168		$ 612
Foreign currency gain	6,069	(194)	9,056	97
Other income, net	(435)	2,264	4	2,274
Total other income	$ 5,802	$ 3,795	$ 9,672	$ 5,207

Income (expense) related to nonoperating activities, classified as other.

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The amount of unusual or infrequent item arising out of COVID relief.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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Amount of realized and unrealized gain (loss) on investment.

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Amount of income (expense) related to nonoperating activities, classified as other.

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