ACCUMULATED OTHER COMPREHENSIVE (LOSS) INCOME - Accumulated Other Comprehensive (Loss) Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Accumulated Other Comprehensive Loss
Balance at beginning of period			$ 1,312,941
Other comprehensive income (loss) before reclassifications	$ (2,681)	$ 187	(2,302)	$ (902)
Amounts reclassified to earnings				(52)
Net current period other comprehensive income				(954)
Balance at end of period	1,323,283		1,323,283
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Loss
Balance at beginning of period	(1,482)	1,091	(1,861)	2,232
Balance at end of period	(4,163)	1,278	(4,163)	1,278
Foreign Currency Translation Adjustment
Accumulated Other Comprehensive Loss
Balance at beginning of period	(1,482)	1,091	(1,864)	2,232
Other comprehensive income (loss) before reclassifications	(2,681)	190	(2,299)	(899)
Amounts reclassified to earnings				(52)
Net current period other comprehensive income				(951)
Balance at end of period	(4,163)	1,281	(4,163)	1,281
Unrealized Gains (Losses) On Available-For-Sale Debt Securities
Accumulated Other Comprehensive Loss
Balance at beginning of period		0	3	0
Other comprehensive income (loss) before reclassifications		(3)	(3)	(3)
Amounts reclassified to earnings				0
Net current period other comprehensive income				(3)
Balance at end of period	$ 0	$ (3)	$ 0	$ (3)

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

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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