INCOME TAXES - Activity related to unrecognized tax benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Activity related to unrecognized tax benefits
Unrecognized benefit - beginning of period	$ 20,635	$ 11,647
Gross increases - prior-period tax positions	21	4
Gross decreases - prior-period tax positions	(2)
Gross increases - current-period tax positions	22,382	8,995
Gross decrease - current-period tax positions		(11)
Statute lapse	(142)
Unrecognized benefit - end of period	$ 42,894	$ 20,635

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

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-Publisher FASB
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-SubTopic 10
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Amount of decrease in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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