Equity Incentive Plans - Schedule of Stock Option Plan Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Options Outstanding, Shares Available for Grant, Beginning balance	4,810,271	3,154,755	92,278
Options Outstanding, Shares Available for Grant, Authorized	2,543,513	6,494,292	5,071,079
Options Outstanding, Shares Available for Grant, RSU granted, net	(657,200)
Options Outstanding, Shares Available for Grant, Granted	(1,760,210)	(4,893,562)	(2,019,598)
Options Outstanding, Shares Available for Grant, Canceled	75,085	54,786	10,996
Options Outstanding, Shares Available for Grant, Ending balance	5,011,459	4,810,271	3,154,755
Options Outstanding, Number of Options, Beginning balance	9,931,229	5,970,382	4,029,331
Options Outstanding, Number of Options, Granted	1,760,210	4,893,562	2,019,598
Options Outstanding, Number of Options, Exercised	(873,735)	(836,241)	(66,499)
Options Outstanding, Number of Options, Canceled	(127,548)	(96,474)	(12,048)
Options Outstanding, Number of Options, Ending balance	10,690,156	9,931,229	5,970,382
Options Outstanding, Number Options, Options exercisable	5,688,319
Options Outstanding, Number of Options, Options vested and expected to vest	10,440,713
Options Outstanding, Weighted-Average Exercise Price, Beginning balance	$ 5.29	$ 0.80	$ 0.72
Options Outstanding, Weighted-Average Exercise Price, Granted	12.43	9.94	1.00
Options Outstanding, Weighted-Average Exercise Price, Exercised	1.03	0.82	0.74
Options Outstanding, Weighted-Average Exercise Price, Canceled	18.87	1.74	9.33
Options Outstanding, Weighted-Average Exercise Price, Ending balance	6.65	$ 5.29	$ 0.80
Options Outstanding, Weighted-Average Exercise Price, Options exercisable	3.95
Options Outstanding, Weighted-Average Exercise Price, Options vested and expected to vest	$ 6.54
Options Outstanding, Aggregate Intrinsic Value, Balance	$ 74,984	$ 229,591	$ 4,335	$ 985
Options Outstanding, Aggregate Intrinsic Value, Options exercisable—December 31, 2016	50,871
Options Outstanding, Aggregate Intrinsic Value, Options vested and expected to vest—December 31, 2016	$ 74,087