CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Net revenues:
Revenues	$ 103,319	$ 97,937
Cost of revenues:
Cost, Amortization	1,950	1,950
Total cost of revenues	42,037	42,230
Gross profit	61,282	55,707
Operating expenses:
Research and development	16,285	15,685
Marketing and selling	24,878	26,132
General and administrative	13,788	13,955
Amortization of intangible assets	363	363
Restructuring costs, net	558	2,907
Total operating expenses	55,872	59,042
Operating (loss) income	5,410	(3,335)
Interest and other expense, net	(5,185)	(5,359)
(Loss) income before income taxes	225	(8,694)
Provision for income taxes	438	255
Net (loss) income	$ (213)	$ (8,949)
Net (loss) income per common share - basic	$ (0.01)	$ (0.22)
Weighted-average common shares outstanding – basic	42,046	41,404
Product [Member]
Net revenues:
Revenues	$ 54,396	$ 46,410
Cost of revenues:
Services	27,600	26,295
Service [Member]
Net revenues:
Revenues	48,923	51,527
Cost of revenues:
Services	$ 12,487	$ 13,985