INCOME TAXES - Reconciliation of Unrecognized Income Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits, beginning balance	$ 8,020	$ 6,599	$ 3,721
Additions for tax positions of prior years	459	576	1,754
Additions for tax positions of current years	1,248	1,646	1,589
Expiration of the statute of limitations	(1,024)	(788)	(439)
Reductions for tax positions of prior years	(52)	(13)	(26)
Unrecognized tax benefits, ending balance	$ 8,651	$ 8,020	$ 6,599

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

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