INCOME TAXES - Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current:
United States-Federal									$ (1,559)	$ 24,546	$ 375
United States-State									(336)	4,506	500
Foreign									8,192	13,060	11,289
Total current income tax expense									6,297	42,112	12,164
Deferred:
United States-Federal									(1,805)	(17,947)	(10,892)
United States-State									(93)	(2,832)	950
Foreign									(294)	(2,463)	(3,563)
Total deferred income tax expense (benefit)									(2,192)	(23,242)	(13,505)
Consolidated:
United States-Federal									(3,364)	6,599	(10,517)
United States-State									(429)	1,674	1,450
Foreign									7,898	10,597	7,726
Total income tax expense (benefit)	$ 1,332	$ 1,834	$ (274)	$ 1,213	$ 5,851	$ 7,010	$ 2,088	$ 3,921	4,105	18,870	$ (1,341)
Deferred tax assets:
Receivables reserve	1,192				3,087				1,192	3,087
Temporary differences not currently deductible for tax	13,144				9,035				13,144	9,035
Deferred compensation	760				784				760	784
Operating lease liability	15,869								15,869
Pension	515				635				515	635
Net operating losses	40,492				29,496				40,492	29,496
Tax Credits	1,511				645				1,511	645
Total deferred tax asset	73,483				43,682				73,483	43,682
Deferred tax liabilities:
Property, plant and equipment, net	15,892				14,608				15,892	14,608
Right-of-use asset	15,869								15,869
Intangible assets, net	8,414				5,959				8,414	5,959
Total deferred tax liabilities	40,175				20,567				40,175	20,567
Valuation allowance	(39,406)				(31,442)				(39,406)	(31,442)
Net deferred tax liabilities	(6,098)				(8,327)				(6,098)	(8,327)
Deferred tax assets:
Total deferred tax asset	2,582				1,949				2,582	1,949
Deferred tax liabilities:
Total deferred tax liabilities	(8,680)				(10,276)				(8,680)	(10,276)
Net deferred tax liabilities	$ (6,098)				$ (8,327)				$ (6,098)	$ (8,327)