Share-Based Payments - 2019 Inducement Share Incentive Plan (Details) - 2019 Inducement Plan - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 12, 2019
Share-Based Payments
Shares available for grant	2,000,000
Unrecognized compensation expense
Total unrecognized compensation related to unvested options	$ 59,000
Recognition period	4 years
Ordinary Shares
Share-Based Payments
Shares reserved for future issuance		2,000,000
Stock Options
Options
Outstanding at beginning of year (in shares)	0
Granted (in shares)	41,150
Exercised (in shares)	0
Forfeited (in shares)	0
Outstanding at end of year (in shares)	41,150
Vested and exercisable at end of year (in shares)	0
Weighted average exercise price in $ per share
Outstanding balance at beginning of year (in dollars per share)	$ 0.00
Granted (in dollars per share)	2.44
Exercised (in dollars per share)	0.00
Forfeited (in dollars per share)	0.00
Outstanding balance at end of year (in dollars per share)	2.44
Vested and exercisable balance at end of year (in dollars per share)	0.00
Aggregate intrinsic value
Weighted-average grant date fair value (in dollars per share)	$ 1.42
Fair Value Assumptions
Expected volatility (as a percent)	61.60%
Expected term of options (in years)	6 years 1 month 6 days
Risk-free interest rate (as a percent)	2.27%
Dividend yield (as a percent)	0.00%
Weighted-average remaining contractual life	10 years
Stock Options | Maximum
Share-Based Payments
Exercise period	10 years
SARs | Maximum
Share-Based Payments
Exercise period	10 years