Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Current Assets:
Cash and cash equivalents	$ 98,810	$ 81,047
Marketable investments (Note 4)	134,876	136,991
Accounts receivable, net (Note 12)	74,623	81,378
Deferred commissions	9,410	12,010
Prepaid expenses and other current assets	18,846	25,935
Total current assets	336,565	337,361
Long-term marketable investments (Note 4)	8,970	9,565
Property and equipment, net (Note 12)	46,300	50,448
Goodwill (Note 3)	78,954	71,543
Intangible assets, net (Note 3)	7,920	10,317
Other assets	9,123	8,344
Total assets	487,832	487,578
Current Liabilities:
Accounts payable	772	1,223
Accrued expenses and other current liabilities (Note 12)	30,078	30,153
Deferred revenue	150,479	147,887
Total current liabilities	181,329	179,263
Non-current liabilities (Note 12)	9,433	17,580
Total liabilities	190,762	196,843
Commitments (Note 7)
Stockholders' Equity (Note 8):
Preferred stock, $.01 par value, Authorized - 500 shares, issued and outstanding - none
Common stock, $.01 par value Authorized - 125,000 shares, Issued - 31,451 and 30,962 in 2012 and 2011, respectively Outstanding - 22,293 and 22,747 in 2012 and 2011, respectively	315	310
Additional paid-in capital	389,362	373,591
Retained earnings	117,648	104,662
Treasury stock - 9,158 and 8,215 in 2012 and 2011, respectively, at cost	(210,843)	(181,000)
Accumulated other comprehensive income (loss)	588	(6,828)
Total stockholders' equity	297,070	290,735
Total liabilities and stockholders' equity	$ 487,832	$ 487,578