Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Revenues	$ 345,321	$ 281,856	$ 996,075	$ 834,798
Costs and operating expenses:
Cost of revenues	109,995	93,284	320,018	271,999
Research and development	19,351	13,542	54,373	37,142
Sales and marketing	75,924	54,520	219,096	160,722
General and administrative	54,511	50,834	168,214	140,710
Amortization of other intangible assets	5,381	4,185	15,611	12,754
Restructuring charge	0	158	14	158
Total costs and operating expenses	265,162	216,523	777,326	623,485
Income from operations	80,159	65,333	218,749	211,313
Interest income	1,568	2,703	4,823	8,675
Other (expense) income, net	(241)	(188)	449	(1,330)
Gain on investments, net	25	299	42	383
Income before provision for income taxes	81,511	68,147	224,063	219,041
Provision for income taxes	33,280	25,862	88,366	78,218
Net income	$ 48,231	$ 42,285	$ 135,697	$ 140,823
Net income per weighted average share:
Basic (in dollars per share)	$ 0.27	$ 0.23	$ 0.76	$ 0.76
Diluted (in dollars per share)	$ 0.27	$ 0.23	$ 0.75	$ 0.74
Shares used in per share calculations:
Basic (in shares)	177,455	183,085	178,040	185,515
Diluted (in shares)	181,053	185,704	181,738	189,089