Share-based Compensation - Options (Details) $ / shares in Units, $ in Millions	6 Months Ended
	Jun. 30, 2020 USD ($) $ / shares shares
Weighted Average Exercise Price
Weighted average contractual term	8 years 8 months 1 day
Stock Options
Number of Shares
Options outstanding, beginning balance (in shares) | shares	380,180
Granted (in shares) | shares	233,888
Exercised (in shares) | shares	(13,020)
Forfeited (in shares) | shares	(9,626)
Options outstanding, ending balance (in shares) | shares	591,422
Options vested and exercisable (in shares) | shares	196,185
Weighted Average Exercise Price
Options outstanding, beginning balance (in dollars per share) | $ / shares	$ 26.01
Granted (in dollars per share) | $ / shares	20.92
Exercised (in dollars per share) | $ / shares	22.31
Forfeited (in dollars per share) | $ / shares	31.99
Options outstanding, ending balance (in dollars per share) | $ / shares	23.98
Options vested and exercisable (in dollars per share) | $ / shares	$ 24.61
Unrecognized compensation expense | $	$ 3.2
Weighted-average period for recognition of compensation cost	2 years 14 days