Equity Incentive Plans - Summary of Stock Option Activity Under 2016 Plan, 2011 Plan and 2007 Plan (Details) - Stock Option $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) $ / shares shares
Options Outstanding
Outstanding at beginning of period | shares	11,203,000
Options granted | shares	451,000
Options exercised | shares	(3,339,000)
Options forfeited or canceled | shares	(825,000)
Outstanding at end of period | shares	7,490,000
Vested and expected to vest at end of period | shares	7,410,000
Exercisable at end of period | shares	4,935,000
Weighted Average Exercise Price per Share
Outstanding at beginning of period | $ / shares	$ 9.49
Options granted | $ / shares	16.97
Options exercised | $ / shares	6.56
Options forfeited or canceled | $ / shares	13.84
Outstanding at end of period | $ / shares	10.76
Vested and expected to vest at end of period | $ / shares	10.71
Exercisable at end of period | $ / shares	$ 8.74
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Outstanding	6 years 4 months 28 days
Vested and expected to vest at end of period	6 years 4 months 20 days
Exercisable at end of period	5 years 6 months 10 days
Total Intrinsic Value | $	$ 95,553
Vested and expected to vest at end of period | $	94,925
Exercisable at end of period | $	$ 72,930