CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Net revenues:
Products	$ 46,379	$ 47,655	$ 92,789	$ 98,661
Services	52,236	54,718	103,763	107,819
Total net revenues	98,615	102,373	196,552	206,480
Cost of revenues:
Products	26,347	26,489	52,642	50,993
Services	13,986	14,181	27,971	28,275
Amortization of intangible assets	1,950	1,950	3,900	3,900
Total cost of revenues	42,283	42,620	84,513	83,168
Gross profit	56,332	59,753	112,039	123,312
Operating expenses:
Research and development	15,985	16,991	31,670	35,879
Marketing and selling	27,759	29,018	53,891	54,829
General and administrative	14,041	13,644	27,996	28,075
Amortization of intangible assets	363	363	726	726
Restructuring costs, net	268	6,063	3,175	7,046
Total operating expenses	58,416	66,079	117,458	126,555
Operating (loss) income	(2,084)	(6,326)	(5,419)	(3,243)
Interest and other expense, net	(6,278)	(3,918)	(11,637)	(8,764)
(Loss) income before income taxes	(8,362)	(10,244)	(17,056)	(12,007)
Provision for income taxes	144	587	399	739
Net (loss) income	$ (8,506)	$ (10,831)	$ (17,455)	$ (12,746)
Net (loss) income per common share - basic	$ (0.20)	$ (0.26)	$ (0.42)	$ (0.31)
Weighted-average common shares outstanding – basic	41,587	40,953	41,496	40,863
Weighted-average common shares outstanding – diluted	41,587	40,953	41,496	40,863