Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Total revenue	$ 106,456	$ 100,406	$ 336,480	$ 335,038
Total cost of revenue	29,036	31,741	88,614	95,649
Gross profit	77,420	68,665	247,866	239,389
Operating expenses:
Research and development	30,678	29,667	91,115	87,012
Sales and marketing	26,998	25,790	80,903	78,462
General and administrative	20,905	20,706	63,499	60,886
Amortization of intangible assets	3,858	3,545	11,390	10,673
Other operating income, net	(1,596)	(536)	(3,431)	(1,702)
Total operating expenses	80,843	79,172	243,476	235,331
Operating (loss) income	(3,423)	(10,507)	4,390	4,058
Interest expense	2,934	2,726	8,590	3,586
Other income, net	(782)	(588)	(1,852)	(703)
(Loss) income before income taxes	(5,575)	(12,645)	(2,348)	1,175
Income tax expense	2,930	3,294	10,350	7,215
Net loss	$ (8,505)	$ (15,939)	$ (12,698)	$ (6,040)
Loss per share:
Net loss per share attributable to common stockholders, basic and diluted	$ (0.12)	$ (0.22)	$ (0.17)	$ (0.08)
Weighted average shares outstanding:
Weighted average number of shares used in computing net loss per share, basic and diluted	73,311	71,770	72,979	71,313
License [Member]
Total revenue	$ 55,023	$ 46,853	$ 183,584	$ 180,127
Total cost of revenue	4,477	4,371	12,851	13,146
Maintenance and Other Services [Member]
Total revenue	32,787	30,963	94,502	85,388
Total cost of revenue	9,626	9,548	28,583	27,509
Total Software [Member]
Total revenue	87,810	77,816	278,086	265,515
Total cost of revenue	14,103	13,919	41,434	40,655
Software Related Services [Member]
Total revenue	6,170	7,956	18,548	25,635
Total cost of revenue	4,996	6,013	15,141	19,143
Total Software and Related Services [Member]
Total revenue	93,980	85,772	296,634	291,150
Total cost of revenue	19,099	19,932	56,575	59,798
Client Engineering Services [Member]
Total revenue	10,868	12,803	34,386	37,265
Total cost of revenue	8,510	10,160	27,617	29,993
Other [Member]
Total revenue	1,608	1,831	5,460	6,623
Total cost of revenue	$ 1,427	$ 1,649	$ 4,422	$ 5,858