Share-Based Payments - 2019 Inducement Share Incentive Plan (Details) - 2019 Inducement Plan - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Mar. 12, 2019
Options
Granted (in shares)		595,150
Forfeited (in shares)		(10,000)
Outstanding at end of year (in shares)	585,150	585,150
Weighted average exercise price in $ per share
Granted (in dollars per share)		$ 2.27
Forfeited (in dollars per share)		2.02
Outstanding balance at end of year (in dollars per share)	$ 2.27	$ 2.27
Aggregate intrinsic value
Share-based compensation expense	$ 30	$ 44
Unrecognized compensation expense
Total unrecognized compensation related to unvested options	$ 700	$ 700
Recognition period		3 years 9 months 18 days
Ordinary Shares
Share-Based Payments
Shares reserved for future issuance	1,414,850	1,414,850	2,000,000
Aggregate intrinsic value
Weighted-average grant date fair value (in dollars per share)		$ 1.40
Stock Options
Fair Value Assumptions
Expected volatility (as a percent)		59.80%
Expected term of options (in years)		6 years 1 month 6 days
Risk-free interest rate (as a percent)		2.90%
Weighted-average remaining contractual life		9 years 9 months 18 days
Stock Options | Minimum
Fair Value Assumptions
Expected volatility (as a percent)		61.60%
Risk-free interest rate (as a percent)		1.42%
Stock Options | Maximum
Fair Value Assumptions
Expected volatility (as a percent)		63.70%
Risk-free interest rate (as a percent)		2.34%