CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Capital in excess of Par Value	Retained Earnings (accumulated deficit)	Accumulated Other Comprehensive Loss	Treasury Stock
Balance (in shares) at Dec. 31, 2017		17,677,000				(1,708,000)
Balance at Dec. 31, 2017	$ 68,986	$ 354	$ 48,349	$ 29,549	$ (3,430)	$ (5,836)
Net income (loss)	68			68
Equity based compensation	181		181
Foreign currency translation adjustments	423				423
Balance (in shares) at Mar. 31, 2018		17,677,000				(1,708,000)
Balance at Mar. 31, 2018	69,658	$ 354	48,530	29,617	(3,007)	$ (5,836)
Balance (in shares) at Dec. 31, 2017		17,677,000				(1,708,000)
Balance at Dec. 31, 2017	68,986	$ 354	48,349	29,549	(3,430)	$ (5,836)
Net income (loss)	(17,959)
Foreign currency translation adjustments	(485)
Balance (in shares) at Sep. 30, 2018		17,869,000				(1,708,000)
Balance at Sep. 30, 2018	52,045	$ 357	49,849	11,590	(3,915)	$ (5,836)
Balance (in shares) at Mar. 31, 2018		17,677,000				(1,708,000)
Balance at Mar. 31, 2018	69,658	$ 354	48,530	29,617	(3,007)	$ (5,836)
Net income (loss)	(1,323)			(1,323)
Issuance of common stock upon the exercise of stock options (in shares)		208,000
Issuance of common stock upon the exercise of stock options	731	$ 3	728
Equity based compensation	250		250
Foreign currency translation adjustments	(625)				(625)
Balance (in shares) at Jun. 30, 2018		17,885,000				(1,708,000)
Balance at Jun. 30, 2018	68,691	$ 357	49,508	28,294	(3,632)	$ (5,836)
Net income (loss)	(16,704)			(16,704)
Issuance of common stock upon the exercise of stock options (in shares)		(16,000)
Issuance of common stock upon the exercise of stock options	18	$ 0	18
Equity based compensation	323		323
Foreign currency translation adjustments	(283)				(283)
Balance (in shares) at Sep. 30, 2018		17,869,000				(1,708,000)
Balance at Sep. 30, 2018	$ 52,045	$ 357	49,849	11,590	(3,915)	$ (5,836)
Balance (in shares) at Dec. 31, 2018	16,171,652	17,878,000				(1,708,000)
Balance at Dec. 31, 2018	$ 45,946	$ 357	50,251	5,427	(4,253)	$ (5,836)
Net income (loss)	(2,729)			(2,729)
Issuance of common stock upon the exercise of stock options (in shares)		78,000
Issuance of common stock upon the exercise of stock options	30	$ 0	30
Equity based compensation	248		248
Foreign currency translation adjustments	(10)				(10)
Balance (in shares) at Mar. 31, 2019		17,956,000				(1,708,000)
Balance at Mar. 31, 2019	$ 43,485	$ 357	50,529	2,698	(4,263)	$ (5,836)
Balance (in shares) at Dec. 31, 2018	16,171,652	17,878,000				(1,708,000)
Balance at Dec. 31, 2018	$ 45,946	$ 357	50,251	5,427	(4,253)	$ (5,836)
Net income (loss)	(9,740)
Foreign currency translation adjustments	$ (236)
Balance (in shares) at Sep. 30, 2019	16,345,368	18,053,000				(1,708,000)
Balance at Sep. 30, 2019	$ 50,556	$ 362	64,832	(4,313)	(4,489)	$ (5,836)
Balance (in shares) at Mar. 31, 2019		17,956,000				(1,708,000)
Balance at Mar. 31, 2019	43,485	$ 357	50,529	2,698	(4,263)	$ (5,836)
Net income (loss)	(1,109)			(1,109)
Issuance of common stock upon the exercise of stock options (in shares)		79,000
Issuance of common stock upon the exercise of stock options	213	$ 3	210
Equity based compensation	602		602
Foreign currency translation adjustments	131				131
Convertible notes conversion discount	12,465
Balance (in shares) at Jun. 30, 2019		18,035,000				(1,708,000)
Balance at Jun. 30, 2019	55,787	$ 360	63,806	1,589	(4,132)	$ (5,836)
Net income (loss)	(5,902)
Issuance of common stock upon the exercise of stock options	40	$ 2	38
Equity based compensation	988		988
Foreign currency translation adjustments	$ (357)				(357)
Balance (in shares) at Sep. 30, 2019	16,345,368	18,053,000				(1,708,000)
Balance at Sep. 30, 2019	$ 50,556	$ 362	$ 64,832	$ (4,313)	$ (4,489)	$ (5,836)