Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
ASSETS
Cash and cash equivalents	$ 193,126	$ 218,680
Short-term investments	100,846	105,054
Accounts receivable, net of allowances of $3,216 and $3,213, respectively	56,164	37,285
Prepaid expenses and other current assets	15,891	15,388
Deferred income taxes	2,438	1,092
Total current assets	368,465	377,499
Long-term investments	16,118	19,841
Property and equipment, net	24,874	19,599
Tradenames, net	85,060	71,409
Patent and patent licenses, net	18,540	19,329
Customer relationships, net	80,761	64,723
Goodwill	429,293	407,825
Other purchased intangibles, net	11,284	9,855
Deferred income taxes	2,165	1,852
Other assets	3,266	3,238
Total assets	1,039,826	995,170
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	57,122	39,874
Income taxes payable	3,277	3,037
Deferred revenue	32,753	30,493
Liability for uncertain tax positions	5,532	5,523
Deferred income taxes	1,107	0
Total current liabilities	99,791	78,927
Long-term Debt	245,310	245,194
Liability for uncertain tax positions	33,439	32,155
Deferred income taxes	39,163	32,393
Other long-term liabilities	3,001	3,166
Mandatorily redeemable financial instrument	9,068	8,740
Total liabilities	429,772	400,575
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 March 31, 2013 and December 31, 2012; total issued 45,292,836 and 45,094,191 shares at March 31, 2013 and December 31, 2012, respectively; and total outstanding 45,292,836 and 45,094,191 shares at March 31, 2013 and December 31, 2012, respectively	453	451
Additional paid-in capital	173,231	169,542
Retained Earnings (Accumulated Deficit)	435,976	424,790
Accumulated other comprehensive loss	980	(88)
Total stockholders' equity	610,640	594,695
Stockholders' Equity Attributable to Noncontrolling Interest	(586)	(100)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	610,054	594,595
Total liabilities and stockholders' equity	$ 1,039,826	$ 995,170