CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Statement [Abstract]
Total revenues	$ 214,801	$ 163,148	$ 411,611	$ 309,823
Cost of revenues	79,807	47,178	150,288	88,265
Gross profit	134,994	115,970	261,323	221,558
Operating expenses:
Research and development	82,324	62,576	153,358	120,694
Sales and marketing	32,576	23,366	63,804	45,924
General and administrative	13,494	10,670	41,432	20,371
Total operating expenses	128,394	96,612	258,594	186,989
Income from operations	6,600	19,358	2,729	34,569
Interest expense	(2,215)	0	(3,213)	0
Other income (loss)	315	912	376	(1,557)
Other income (loss), net	(1,900)	912	(2,837)	(1,557)
Income (loss) before taxes on income	4,700	20,270	(108)	33,012
Provision for taxes on income	46	1,022	2,406	3,268
Net income (loss)	$ 4,654	$ 19,248	$ (2,514)	$ 29,744
Net income (loss) per share - basic (in USD per share)	$ 0.10	$ 0.42	$ (0.05)	$ 0.65
Net income (loss) per share - diluted (in USD per share)	$ 0.09	$ 0.40	$ (0.05)	$ 0.63
Shares used in computing income (loss) per share:
Basic (in shares)	47,900	46,191	47,629	45,943
Diluted (in shares)	49,194	47,568	47,629	47,341