Stock-based Compensation Stock-based Compensation - Schedule of Stock Options Activity (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) $ / shares shares
NUMBER OF SHARES
Options outstanding at beginning of year (in shares) | shares	3,826,459
Granted (in shares) | shares	1,328,400
Exercised (in shares) | shares	(297,763)
Canceled (in shares) | shares	(273,510)
Options outstanding at end of year (in shares) | shares	4,583,586
Options vested and expected to vest (in shares) | shares	4,511,052
Options exercisable at end of year (in shares) | shares	2,237,663
WEIGHTED AVERAGE EXERCISE PRICE
Options outstanding at beginning of year, weighted average exercise price (in dollars per share) | $ / shares	$ 8.39
Granted (in dollars per share) | $ / shares	24.83
Exercised (in dollars per share) | $ / shares	4.38
Canceled (in dollars per share) | $ / shares	17.00
Options outstanding at end of year, weighted average exercise price (in dollars per share) | $ / shares	12.86
Options vested and expected to vest (in dollars per share) | $ / shares	12.75
Options exercisable, weighted average exercise price (in dollars per share) | $ / shares	$ 7.92
WEIGHTED AVERAGE REMAINING CONTRACTUAL LIFE (YEARS)
Options outstanding (in years)	7 years 11 months 27 days
Options vested and expected to vest (in years)	7 years 11 months 23 days
Options exercisable (in years)	7 years 4 months 2 days
AGGREGATE INTRINSIC VALUE
Options outstanding | $	$ 55,918
Options vested and expected to vest | $	55,478
Options exercisable | $	$ 37,308