ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Summary (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Accumulated Other Comprehensive Loss
Balance at beginning of period			$ 993,346
Other comprehensive (loss) income before reclassifications	$ (4,942)	$ 330	(1,089)	$ 1,491
Amounts reclassified to earnings	(191)	0	(52)	0
Net current period other comprehensive (loss) income	(5,133)	330	(1,141)	1,491
Balance at end of period	1,058,409		1,058,409
Accumulated Other Comprehensive (Loss) Income
Accumulated Other Comprehensive Loss
Balance at beginning of period	6,224	(560)	2,232	(1,721)
Balance at end of period	$ 1,091	$ (230)	$ 1,091	$ (230)

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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