Equity Incentive Plans - Summary of Stock Option Activity (Details) - Stock Option $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2017 USD ($) $ / shares shares
Options Outstanding
Outstanding at beginning of period | shares	11,203,000
Options granted | shares	291,000
Options exercised | shares	(1,402,000)
Options forfeited or canceled | shares	(616,000)
Outstanding at end of period | shares	9,476,000
Vested and expected to vest at end of period | shares	9,393,000
Exercisable at end of period | shares	6,061,000
Weighted Average Exercise Price per Share
Outstanding at beginning of period | $ / shares	$ 9.49
Options granted | $ / shares	14.08
Options exercised | $ / shares	3.95
Options forfeited or canceled | $ / shares	13.86
Outstanding at end of period | $ / shares	10.16
Vested and expected to vest at end of period | $ / shares	10.12
Exercisable at end of period | $ / shares	$ 8.01
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Outstanding	6 years 8 months 19 days
Vested and expected to vest at end of period	6 years 7 months 28 days
Exercisable at end of period	5 years 7 months 21 days
Total Intrinsic Value | $	$ 68,169
Vested and expected to vest at end of period | $	67,963
Exercisable at end of period | $	$ 56,624