Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
ASSETS
Cash and cash equivalents	$ 142,873	$ 139,359
Short-term investments	41,744	38,513
Accounts receivable, net of allowances of $4,172 and $3,404, respectively	20,242	19,071
Prepaid expenses and other current assets	6,215	14,311
Deferred income taxes	2,151	1,643
Total current assets	213,225	212,897
Long-term investments	22,217	43,077
Property and equipment, net	14,095	14,438
Tradenames, net	34,494	34,691
Patent and patent licenses, net	18,067	17,517
Customer relationships, net	40,045	35,865
Goodwill	289,259	279,016
Other purchased intangibles, net	9,306	9,994
Deferred income taxes	6,144	3,160
Other assets	2,429	516
Total assets	649,281	651,171
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	26,236	24,070
Income taxes payable	3,697	1,510
Deferred revenue	28,366	26,695
Liability for uncertain tax positions	5,523	5,523
Total current liabilities	63,822	57,798
Liability for uncertain tax positions	28,144	24,554
Deferred income taxes	11,305	12,102
Other long-term liabilities	2,500	2,342
Total liabilities	105,771	96,796
Commitments and contingencies	0	0
Preferred stock, $0.01 par value. Authorized 1,000,000 and none issued	0	0
Common stock, $0.01 par value. Authorized 95,000,000 at June 30, 2012 and December 31, 2011; total issued 53,623,637 and 55,389,636 shares at June 30, 2012 and December 31, 2011, respectively; and total outstanding 44,943,069 and 46,709,068 shares at June 30, 2012 and December 31, 2011, respectively	536	554
Additional paid-in capital	195,538	197,374
Treasury stock, at cost (8,680,568 shares at June 30, 2012 and December 31, 2011)	(112,671)	(112,671)
Retained earnings	462,658	472,595
Accumulated other comprehensive loss	(2,551)	(3,477)
Total stockholders' equity	543,510	554,375
Total liabilities and stockholders' equity	$ 649,281	$ 651,171