Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 144,724	$ 559,197
Marketable securities (including restricted securities of $51 and $272 at September 30, 2011 and December 31, 2010, respectively)	259,818	290,029
Accounts receivable, net of reserves of $5,676 and $5,232 at September 30, 2011 and December 31, 2010, respectively	215,855	210,936
Prepaid expenses and other current assets	52,700	55,414
Deferred income tax assets	6,444	6,444
Total current assets	679,541	1,122,020
Property and equipment, net	303,518	293,043
Marketable securities (including restricted securities of $45 at September 30, 2011 and December 31, 2010)	574,178	380,729
Goodwill	709,628	452,914
Other intangible assets, net	89,519	45,386
Deferred income tax assets	43,274	43,485
Other assets	14,460	7,924
Total assets	2,414,118	2,345,501
Current liabilities:
Accounts payable	32,944	38,247
Accrued expenses and other current liabilities	91,076	85,371
Deferred revenue	23,192	21,344
Accrued restructuring	1,326	3,430
Total current liabilities	148,538	148,392
Other liabilities	62,165	38,389
Deferred revenue	2,227	2,470
Total liabilities	212,930	189,251
Commitments, contingencies and guarantees (Note 15)
Stockholders' equity:
Preferred stock, $0.01 par value; 5,000,000 shares authorized; 700,000 shares designated as Series A Junior Participating Preferred Stock; no shares issued or outstanding	0	0
Common stock, $0.01 par value; 700,000,000 shares authorized; 194,682,252 shares issued and 179,519,564 shares outstanding at September 30, 2011 and 192,383,121 shares issued and 186,603,380 shares outstanding at December 31, 2010	1,982	1,959
Additional paid-in capital	5,076,885	5,068,235
Accumulated other comprehensive income (loss)	(307)	(1,259)
Treasury stock, at cost, 15,162,688 shares at September 30, 2011 and 5,779,741 shares at December 31, 2010	(490,908)	(482,994)
Accumulated deficit	(2,386,464)	(2,429,691)
Total stockholders' equity	2,201,188	2,156,250
Total liabilities and stockholders' equity	$ 2,414,118	$ 2,345,501