CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Net revenues:
Recurring revenues	$ 324,627	$ 291,486	$ 252,054
Non-recurring revenues	34,192	34,762	31,447
Total net revenues	358,819	326,248	283,501
Cost of revenues:
Recurring revenues	68,953	62,329	51,261
Non-recurring revenues	43,505	39,623	29,175
Amortization of developed technology	10,258	8,820	6,374
Total cost of revenues	122,716	110,772	86,810
Gross margin	236,103	215,476	196,691
Operating expenses:
Sales and marketing	74,688	74,807	69,151
Product development	67,014	57,561	51,416
General and administrative	37,763	37,040	37,707
Amortization of other intangibles	3,825	2,807	1,272
Restructuring charges	3,634	696	840
Total operating expenses	186,924	172,911	160,386
Income from continuing operations	49,179	42,565	36,305
Interest expense	(1,973)	(188)	(54)
Interest income and other expense, net	353	(555)	(841)
Loss on equity investments, net		(500)
Income from continuing operations before income taxes	47,559	41,322	35,410
Provision for income taxes	17,328	12,991	11,091
Net income from continuing operations	30,231	28,331	24,319
Discontinued operation:
Net income (loss) from discontinued operation (net of applicable taxes of $126, $1,197 and $(46), respectively)	184	1,839	(166)
Net income	$ 30,415	$ 30,170	$ 24,153
Basic net income per share:
Continuing operations (in dollars per share)	$ 0.60	$ 0.55	$ 0.47
Discontinued operation (in dollars per share)		$ 0.04
Total operations (in dollars per share)	$ 0.60	$ 0.58	$ 0.47
Diluted net income per share:
Continuing operations (in dollars per share)	$ 0.58	$ 0.52	$ 0.45
Discontinued operation (in dollars per share)		$ 0.03
Total operations (in dollars per share)	$ 0.58	$ 0.56	$ 0.44
Weighted average shares used to compute basic and diluted net income per share
Basic (in shares)	50,614	51,797	51,535
Diluted (in shares)	52,425	54,085	54,476