Consolidated statements of operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Total revenue	$ 127,859	$ 113,257
Total cost of revenue	32,885	29,042
Gross profit	94,974	84,215
Operating expenses:
Research and development	27,516	22,703
Sales and marketing	26,451	18,627
General and administrative	20,329	16,990
Amortization of intangible assets	3,528	1,940
Other operating income	(617)	(2,191)
Total operating expenses	77,207	58,069
Operating income	17,767	26,146
Interest expense	270	16
Other expense (income), net	390	(900)
Income before income taxes	17,107	27,030
Income tax expense	4,088	2,346
Net income	$ 13,019	$ 24,684
Income per share:
Net income per share attributable to common stockholders, basic	$ 0.18	$ 0.39
Net income per share attributable to common stockholders, diluted	$ 0.17	$ 0.34
Weighted average shares outstanding:
Weighted average number of shares used in computing net income per share, basic	70,786	63,638
Weighted average number of shares used in computing net income per share, diluted	76,720	72,390
License [Member]
Total revenue	$ 76,621	$ 66,935
Total cost of revenue	5,821	3,730
Maintenance and Other Services [Member]
Total revenue	26,670	22,734
Total cost of revenue	8,531	7,192
Total Software [Member]
Total revenue	103,291	89,669
Total cost of revenue	14,352	10,922
Software Related Services [Member]
Total revenue	9,772	9,473
Total cost of revenue	6,518	6,709
Total Software and Related Services [Member]
Total revenue	113,063	99,142
Total cost of revenue	20,870	17,631
Client Engineering Services [Member]
Total revenue	12,050	12,080
Total cost of revenue	9,800	10,200
Other [Member]
Total revenue	2,746	2,035
Total cost of revenue	$ 2,215	$ 1,211