CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenue:
Software license	$ 275,588	$ 232,336	$ 191,876
Maintenance	202,802	186,239	157,309
Services	204,305	171,429	159,769
Total revenue	682,695	590,004	508,954
Cost of revenue:
Software license	4,125	4,959	6,281
Maintenance	21,903	20,014	15,272
Services	187,418	160,121	135,853
Total cost of revenue	213,446	185,094	157,406
Gross profit	469,249	404,910	351,548
Operating expenses:
Selling and marketing	241,387	206,658	181,094
Research and development	126,374	108,591	79,726
General and administrative	36,738	37,442	29,594
Acquisition-related	89	488	1,306
Restructuring		192	1,731
Total operating expenses	404,588	353,371	293,451
Income from operations	64,661	51,539	58,097
Foreign currency transaction loss	(4,168)	(3,769)	(1,593)
Interest income, net	1,056	683	524
Other expense, net	(1,044)	(459)	(635)
Income before provision for income taxes	60,505	47,994	56,393
Provision for income taxes	24,183	14,739	18,350
Net income	$ 36,322	$ 33,255	$ 38,043
Earnings per share:
Basic	$ 0.47	$ 0.44	$ 0.50
Diluted	$ 0.46	$ 0.42	$ 0.49
Weighted-average number of common shares outstanding
Basic	76,507	76,327	75,946
Diluted	79,043	78,531	77,974