Condensed Consolidated Statements of Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Total
Balance at Dec. 31, 2017	$ 269	$ 294,613	$ (201,541)	$ (5,712)	$ 87,629
Exercise of share options	2	82			84
Share-based compensation expense		1,824			1,824
Tax on vesting of restricted share units		(156)			(156)
Other comprehensive income				557	557
Net loss			(10,326)		(10,326)
Balance at Mar. 31, 2018	271	296,363	(211,867)	(5,155)	79,612
Balance at Dec. 31, 2018	276	303,015	(80,762)	(8,523)	214,006
Exercise of share options	2	1,800			1,802
Share-based compensation expense		845			845
Tax on vesting of restricted share units		(145)			(145)
Other comprehensive income				1,167	1,167
Net loss			(1,496)		(1,496)
Balance at Mar. 31, 2019	$ 278	$ 305,515	$ (82,258)	$ (7,356)	$ 216,179