CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Revenue:
Software licenses	$ 141,087	$ 140,489	$ 267,138	$ 265,458
Maintenance and service	104,982	94,996	204,837	187,808
Total revenue	246,069	235,485	471,975	453,266
Cost of sales:
Software licenses	6,534	6,950	13,272	14,159
Amortization	9,520	9,743	19,031	19,100
Maintenance and service	20,957	21,092	39,993	40,414
Total cost of sales	37,011	37,785	72,296	73,673
Gross profit	209,058	197,700	399,679	379,593
Operating expenses:
Selling, general and administrative	64,259	63,524	122,028	120,273
Research and development	47,443	42,646	92,115	82,655
Amortization	3,201	5,035	6,359	10,112
Total operating expenses	114,903	111,205	220,502	213,040
Operating income	94,155	86,495	179,177	166,553
Interest expense	(59)	(122)	(145)	(276)
Interest income	1,077	795	2,027	1,451
Other income, net	305	91	197	858
Income before income tax provision	95,478	87,259	181,256	168,586
Income tax provision	25,850	24,924	55,160	50,119
Net income	$ 69,628	$ 62,335	$ 126,096	$ 118,467
Earnings per share - basic:
Basic earnings per share	$ 0.79	$ 0.69	$ 1.43	$ 1.32
Weighted average shares - basic	87,638	89,866	87,876	89,962
Earnings per share - diluted:
Diluted earnings per share	$ 0.78	$ 0.68	$ 1.41	$ 1.29
Weighted average shares - diluted	89,305	91,726	89,694	91,933