Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 260,149	$ 280,740
Short-term investments, available-for-sale	529,260	453,976
Accounts receivable, net of allowances of $5,976 and $5,354 at December 31, 2014 and 2013, respectively	674,401	654,821
Inventories, net	12,617	14,107
Prepaid expenses and other current assets	166,005	110,981
Current portion of deferred tax assets, net	45,892	48,470
Total current assets	1,688,324	1,563,095
Long-term investments, available-for-sale	1,073,110	855,700
Property and equipment, net	367,779	338,996
Goodwill	1,796,851	1,768,949
Other intangible assets, net	390,717	509,595
Long-term portion of deferred tax assets, net	128,198	115,418
Other assets	67,028	60,496
Total assets	5,512,007	5,212,249
Current liabilities:
Accounts payable	79,884	78,452
Accrued expenses and other current liabilities	298,079	257,606
Income taxes payable	12,053	29,322
Current portion of deferred revenues	1,200,093	1,098,681
Total current liabilities	1,590,109	1,464,061
Long-term portion of deferred revenues	357,771	313,059
Convertible notes	1,292,953	0
Other liabilities	97,529	115,322
Commitments and contingencies
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; 294,674 and 291,078 shares issued and outstanding at December 31, 2014 and 2013, respectively	295	291
Additional paid-in capital	4,292,706	3,974,297
Retained earnings	3,155,264	2,903,541
Accumulated other comprehensive (loss) income	(36,790)	4,951
Stockholders' equity before treasury stock	7,411,475	6,883,080
Less - common stock in treasury, at cost (133,898 and 107,789 shares at December 31, 2014 and 2013, respectively)	(5,237,830)	(3,563,273)
Total stockholders' equity	2,173,645	3,319,807
Total liabilities and stockholders' equity	$ 5,512,007	$ 5,212,249