Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 362,313	$ 260,149
Short-term investments, available-for-sale	510,178	529,260
Accounts receivable, net of allowances of $4,847 and $5,976 at June 30, 2015 and December 31, 2014, respectively	500,976	674,401
Inventories, net	12,708	12,617
Prepaid expenses and other current assets	154,990	166,005
Current portion of deferred tax assets, net	48,118	45,892
Total current assets	1,589,283	1,688,324
Long-term investments, available-for-sale	972,909	1,073,110
Property and equipment, net	370,767	367,779
Goodwill	1,958,022	1,796,851
Other intangible assets, net	460,538	390,717
Long-term portion of deferred tax assets, net	80,336	128,198
Other assets	70,120	67,028
Total assets	5,501,975	5,512,007
Current liabilities:
Accounts payable	81,966	79,884
Accrued expenses and other current liabilities	262,504	298,079
Income taxes payable	3,716	12,053
Current portion of deferred revenues	1,176,132	1,200,093
Total current liabilities	1,524,318	1,590,109
Long-term portion of deferred revenues	363,412	357,771
Convertible notes	1,308,852	1,292,953
Other liabilities	$ 80,558	$ 97,529
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; 297,179 and 294,674 shares issued and outstanding at June 30, 2015 and December 31, 2014, respectively	297	295
Additional paid-in capital	4,404,630	4,292,706
Retained earnings	3,287,426	3,155,264
Accumulated other comprehensive loss	(29,236)	(36,790)
Stockholders' equity before treasury stock	7,663,117	7,411,475
Less - common stock in treasury, at cost (137,037 and 133,898 shares at June 30, 2015 and December 31, 2014, respectively)	(5,438,282)	(5,237,830)
Total stockholders' equity	2,224,835	2,173,645
Total liabilities and stockholders' equity	$ 5,501,975	$ 5,512,007