PURCHASED INTANGIBLE ASSETS (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Purchased intangible assets
Gross	$ 56,082	$ 54,796
Accumulated Amortization	(51,699)	(48,916)
Net	4,383	5,880
Core technology
Purchased intangible assets
Gross	17,868	17,717
Accumulated Amortization	(13,485)	(11,837)
Net	4,383	5,880
Customer relationships
Purchased intangible assets
Gross	36,139	35,091
Accumulated Amortization	(36,139)	(35,091)
Net	0	0
Trademarks / Trade names
Purchased intangible assets
Gross	2,075	1,988
Accumulated Amortization	(2,075)	(1,988)
Net	$ 0	$ 0