Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 246,473	$ 643,609
Short-term investments, available-for-sale	448,196	285,022
Accounts receivable, net of allowances of $5,371 and $6,448 at September 30, 2013 and December 31, 2012, respectively	450,395	630,956
Inventories, net	11,979	10,723
Prepaid expenses and other current assets	131,927	106,579
Current portion of deferred tax assets, net	39,836	36,846
Total current assets	1,328,806	1,713,735
Long-term investments, available-for-sale	961,422	595,313
Property and equipment, net	337,021	303,294
Goodwill	1,766,902	1,518,219
Other intangible assets, net	533,996	556,205
Long-term portion of deferred tax assets, net	129,983	43,097
Other assets	65,859	66,539
Total assets	5,123,989	4,796,402
Current liabilities:
Accounts payable	68,646	71,116
Accrued expenses and other current liabilities	244,387	257,135
Income taxes payable	25,472	49,346
Current portion of deferred revenues	1,002,090	965,276
Total current liabilities	1,340,595	1,342,873
Long-term portion of deferred revenues	268,086	232,719
Other liabilities	114,508	99,033
Commitments and contingencies
Stockholders' equity:
Preferred stock at $.01 par value: 5,000 shares authorized, none issued and outstanding	0	0
Common stock at $.001 par value: 1,000,000 shares authorized; 290,639 and 287,123 shares issued and outstanding at September 30, 2013 and December 31, 2012, respectively	291	287
Additional paid-in capital	3,948,810	3,691,111
Retained earnings	2,764,897	2,564,018
Accumulated other comprehensive loss	(3,222)	(7,705)
Stockholders' equity before treasury stock	6,710,776	6,247,711
Less - common stock in treasury, at cost (103,410 and 100,781 shares at September 30, 2013 and December 31, 2012, respectively)	(3,309,976)	(3,125,934)
Total stockholders' equity	3,400,800	3,121,777
Total liabilities and equity	$ 5,123,989	$ 4,796,402