Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Revenues	$ 368,046	$ 319,448
Costs and operating expenses:
Cost of revenues	120,392	124,925
Research and development	21,905	17,480
Sales and marketing	62,690	48,995
General and administrative	55,380	51,642
Amortization of other intangible assets	6,060	4,767
Restructuring charge	431	60
Total costs and operating expenses	266,858	247,869
Income from operations	101,188	71,579
Interest income	1,556	1,633
Other (expense) income, net	(132)	(441)
Gain on investments, net	52	13
Income before provision for income taxes	102,664	72,784
Provision for income taxes	31,177	29,557
Net income	$ 71,487	$ 43,227
Net income per weighted average share:
Basic (in dollars per share)	$ 0.40	$ 0.24
Diluted (in dollars per share)	$ 0.39	$ 0.24
Shares used in per share calculations:
Basic (in shares)	177,899	178,120
Diluted (in shares)	181,562	182,342