Condensed Consolidated Balance Sheets (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
ASSETS
Cash and cash equivalents	$ 134,190	$ 64,752
Short-term investments	29,005	14,035
Accounts receivable, net of allowances of $3,527 and $2,588, respectively	17,723	17,423
Prepaid expenses and other current assets	16,145	15,196
Deferred income taxes	3,160	4,096
Total current assets	200,223	115,502
Long-term investments	30,635	8,175
Property and equipment, net	14,335	13,567
Tradenames, net	34,940	33,396
Patent and patent licenses, net	17,608	18,102
Customer relationships, net	37,538	36,674
Goodwill	279,007	281,848
Other purchased intangibles, net	10,283	11,782
Deferred income taxes	11,677	12,967
Other assets	659	610
Total assets	636,905	532,623
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	22,903	25,112
Income taxes payable	2,343	1,798
Deferred revenue	27,275	16,938
Liability for uncertain tax positions	297	13,471
Deferred income taxes	680	573
Total current liabilities	53,498	57,892
Liability for uncertain tax positions	27,897	24,391
Deferred income taxes	20,042	15,293
Other long-term liabilities	3,072	3,302
Total liabilities	104,509	100,878
Commitments and contingencies
Preferred stock, $0.01 par value. Authorized 1,000,000 and none issued
Common stock, $0.01 par value. Authorized 95,000,000 at September 30, 2011 and December 31, 2010; total issued 55,348,571 and 53,700,629 shares at September 30, 2011 and December 31, 2010, respectively; and total outstanding 46,668,003 and 45,020,061 shares at September 30, 2011 and December 31, 2010, respectively	553	537
Additional paid-in capital	194,649	164,769
Treasury stock, at cost (8,680,568 shares at September 30, 2011 and December 31, 2010)	(112,671)	(112,671)
Retained earnings	452,489	381,145
Accumulated other comprehensive loss	(2,624)	(2,035)
Total stockholders' equity	532,396	431,745
Total liabilities and stockholders' equity	$ 636,905	$ 532,623