Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenue:
Product	$ 1,432,810	$ 991,337	$ 744,877
Service	213,376	137,830	92,714
Total revenue	1,646,186	1,129,167	837,591
Cost of revenue:
Product	538,035	369,768	263,585
Service	46,382	36,283	30,446
Total cost of revenue	584,417	406,051	294,031
Gross profit	1,061,769	723,116	543,560
Operating expenses:
Research and development	349,594	273,581	209,448
Sales and marketing	155,105	130,887	109,084
General and administrative	86,798	75,239	75,720
Total operating expenses	591,497	479,707	394,252
Income from operations	470,272	243,409	149,308
Other income (expense), net:
Interest expense	(2,780)	(3,136)	(3,152)
Other income (expense), net	7,268	1,952	(147)
Total other income (expense), net	4,488	(1,184)	(3,299)
Income before income taxes	474,760	242,225	146,009
Provision for income taxes	51,559	58,036	24,907
Net income	423,201	184,189	121,102
Net income attributable to common stockholders:
Basic	422,400	182,965	119,115
Diluted	$ 422,468	$ 183,039	$ 119,264
Net income per share attributable to common stockholders:
Basic (in dollars per share)	$ 5.85	$ 2.66	$ 1.81
Diluted (in dollars per share)	$ 5.35	$ 2.50	$ 1.67
Weighted-average shares used in computing net income per share attributable to common stockholders:
Basic (in shares)	72,258	68,771	65,964
Diluted (in shares)	78,977	73,222	71,411