Stock-Based Compensation - Schedule of Stock-Based Compensation Activity (Details) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding beginning balance (in shares) | shares	3,285
Granted (in shares) | shares	961
Exercised (in shares) | shares	(677)
Canceled/Forfeited (in shares) | shares	(177)
Outstanding ending balance (in shares) | shares	3,392
Exercisable at end of period (in shares) | shares	2,003
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding weighted average exercise price, beginning balance (in usd per share) | $ / shares	$ 15.46
Granted weighted average exercise price (in usd per share) | $ / shares	11.07
Exercised weighted average exercise price (in usd per share) | $ / shares	15.47
Canceled/Forfeited weighted average exercise price (in usd per share) | $ / shares	11.79
Outstanding weighted average exercise price, ending balance (in usd per share) | $ / shares	14.41
Exercisable weighted average exercise price at end of period (in usd per share) | $ / shares	$ 16.53
Outstanding, weighted average remaining term at end of period	7 years 2 months 16 days
Exercisable, weighted average remaining term at end of period	6 years 3 months 4 days
Outstanding, intrinsic value at end of period | $	$ 86,987
Exercisable, intrinsic value at end of period | $	$ 47,116