INTANGIBLE ASSETS (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Amortization of Finite-Lived Intangible Assets	$ 2,300	$ 2,500	$ 6,900	$ 8,000
Amortizing Identifiable Intangible Assets [Abstract]
Gross	119,725		119,725		$ 118,848
Accumulated Amortization	(103,730)		(103,730)		(95,916)
Net	15,995		15,995		22,932
Future expected amortization expense, identifiable intangible assets
2017	2,300		2,300
2018	9,300		9,300
2019	4,400		4,400
Carrying value of Goodwill [Abstract]
Goodwill	32,643		32,643		32,643
Completed Technologies and Patents [Member]
Amortizing Identifiable Intangible Assets [Abstract]
Gross	58,562		58,562		57,994
Accumulated Amortization	(45,074)		(45,074)		(38,657)
Net	13,488		13,488		19,337
Customer Relationships [Member]
Amortizing Identifiable Intangible Assets [Abstract]
Gross	54,906		54,906		54,597
Accumulated Amortization	(52,399)		(52,399)		(51,002)
Net	2,507		2,507		3,595
Trade Names [Member]
Amortizing Identifiable Intangible Assets [Abstract]
Gross	1,346		1,346		1,346
Accumulated Amortization	(1,346)		(1,346)		(1,346)
Net	0		0		0
Capitalized Software Costs [Member]
Amortizing Identifiable Intangible Assets [Abstract]
Gross	4,911		4,911		4,911
Accumulated Amortization	(4,911)		(4,911)		(4,911)
Net	$ 0		$ 0		$ 0