INCOME TAXES - Income Tax Uncertainties (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of unrecognized tax benefits [Roll Forward]
Balance at beginning of period	$ 4,781	$ 6,637	$ 6,570
Increases for tax positions of prior years	1,366	393	332
Decreases for tax positions of prior years	(1,185)	(2,711)	(406)
Increases for tax positions related to current year	747	462	141
Balance at end of period	$ 5,709	$ 4,781	$ 6,637

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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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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- Definition

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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