Share-Based Compensation Summary of Changes in Stock Options Outstanding (Details)	12 Months Ended
	Dec. 31, 2018 USD ($) $ / shares shares
Options Rollforward
Outstanding beginning balance (in shares) | shares	1,644,212
Number of Options, Granted (in shares) | shares	48,400
Exercised (in shares) | shares	(74,722)
Number of Options, Canceled (in shares) | shares	(102,429)
Outstanding ending balance (in shares) | shares	1,515,461
Weighted Average Exercise Price [Abstract]
Weighted Average Exercise Price, beginning balance (in usd per share) | $ / shares	$ 8.81
Options granted, exercise price (in dollars per share) | $ / shares	24.46
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price | $ / shares	10.36
Options canceled, exercise price (in dollars per share) | $ / shares	10.73
Weighted Average Exercise Price, ending balance (in usd per share) | $ / shares	$ 9.11
Weighted Average Remaining Contract Term (years)	6 years 6 months 26 days
Intrinsic Value, Outstanding Shares | $	$ 21,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number | shares	1,102,594
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price | $ / shares	$ 8.15
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term	6 years 2 months 1 day
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value | $	$ 16,369