CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
CONSOLIDATED STATEMENTS OF OPERATIONS
Total revenues	$ 500,799	$ 259,251	$ 154,640
Cost of revenues	157,936	92,015	40,550
Gross profit	342,863	167,236	114,090
Operating expenses:
Research and development	138,946	92,508	56,804
Sales and marketing	61,068	40,366	22,104
General and administrative	24,541	21,769	11,744
Total operating expenses	224,555	154,643	90,652
Income from operations	118,308	12,593	23,438
Other income (loss), net	1,259	759	(135)
Income before taxes on income	119,567	13,352	23,303
Provision for taxes on income	(8,187)	(3,375)	(9,763)
Net income	$ 111,380	$ 9,977	$ 13,540
Net income per share - basic (in dollars per share)	$ 2.70	$ 0.28	$ 0.40
Net income per share - diluted (in dollars per share)	$ 2.54	$ 0.26	$ 0.38
Shares used in computing income per share:
Basic (in shares)	41,308	36,263	33,591
Diluted (in shares)	43,901	38,562	35,483