CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net revenues:
Products	$ 409,944	$ 360,466	$ 411,788
Cost of revenues:
Amortization of intangible assets	0	0	3,738
Total cost of revenues	144,140	132,146	162,713
Gross profit	265,804	228,320	249,075
Operating expenses:
Research and development	65,559	57,018	62,343
Marketing and selling	95,494	87,637	99,944
General and administrative	57,372	47,052	53,362
Amortization of intangible assets	0	0	694
Restructuring costs, net	1,116	5,046	629
Total operating expenses	219,541	196,753	216,972
Operating income	46,263	31,567	32,103
Interest income	6	70	36
Interest expense	(7,155)	(20,071)	(26,712)
Other income (expense), net	4,841	868	(2,902)
(Loss) income before income taxes	43,955	12,434	2,525
Provision for (benefit from) income taxes	2,567	1,372	(5,076)
Net (loss) income	$ 41,388	$ 11,062	$ 7,601
Earnings Per Share, Basic	$ 0.92	$ 0.25	$ 0.18
Earnings Per Share, Diluted	$ 0.89	$ 0.25	$ 0.17
Weighted-average common shares outstanding - basic	45,101	43,822	42,649
Weighted-average common shares outstanding - diluted	46,303	44,878	43,495
Subscription services
Net revenues:
Products	$ 108,443	$ 72,831	$ 45,181
Cost of revenues:
Products	14,963	6,870	3,676
Maintenance services
Net revenues:
Products	122,411	124,175	130,443
Cost of revenues:
Products	22,981	21,651	20,996
Service
Net revenues:
Products	179,090	163,460	236,164
Cost of revenues:
Products	$ 106,196	$ 103,625	$ 134,303