ACCUMULATED OTHER COMPREHENSIVE 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 Income (Loss)
Balances	$ 111,200	$ 95,525	$ 101,813	$ 87,347
Balances	113,796	100,483	113,796	100,483
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss)
Balances	(9,555)	(6,580)	(8,518)	(5,586)
Unrealized gain (loss) on cash flow hedges	(78)	121	(675)	936
Amounts reclassified from AOCI	(27)	16	(128)	52
Foreign currency translation loss	(2,369)	(307)	(2,708)	(2,152)
Balances	(12,029)	(6,750)	(12,029)	(6,750)
Defined Benefit Plan Liability
Accumulated Other Comprehensive Income (Loss)
Balances	(1,006)	(945)	(1,006)	(945)
Balances	(1,006)	(945)	(1,006)	(945)
Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss)
Balances	(264)	1,047	434	196
Unrealized gain (loss) on cash flow hedges	(78)	121	(675)	936
Amounts reclassified from AOCI	(27)	16	(128)	52
Balances	(369)	1,184	(369)	1,184
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss)
Balances	(8,285)	(6,682)	(7,946)	(4,837)
Foreign currency translation loss	(2,369)	(307)	(2,708)	(2,152)
Balances	$ (10,654)	$ (6,989)	$ (10,654)	$ (6,989)

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 gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount, after tax and before reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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

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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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