CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY - USD ($) $ in Thousands	Common Stock	Treasury Stock	Additional Paid-in Capital	Accumulated Deficit	Total
Balance at Dec. 31, 2016	$ 15	$ (1,842)	$ 378,876	$ (308,466)	$ 68,583
Balance (in shares) at Dec. 31, 2016	15,175,767	(273,937)
Increase (Decrease) in Stockholders' Equity
Stock issued for restricted stock (in shares)	190,482
Stock issued under defined contribution 401(k) retirement savings plan			316		316
Stock issued under defined contribution 401(k) retirement savings plan (in shares)	114,050
Share-based compensation			813		813
Net loss				(3,641)	(3,641)
Balance at Dec. 31, 2017	$ 15	$ (1,842)	380,005	(312,107)	$ 66,071
Balance (in shares) at Dec. 31, 2017	15,480,299	(273,937)			15,480,299
Increase (Decrease) in Stockholders' Equity
Stock issued for restricted stock	$ 1				$ 1
Stock issued for restricted stock (in shares)	115,403
Stock issued under defined contribution 401(k) retirement savings plan			338		338
Stock issued under defined contribution 401(k) retirement savings plan (in shares)	148,943
Share-based compensation			489		489
Net loss				(10,954)	(10,954)
Balance at Jun. 30, 2018	$ 16	$ (1,842)	$ 380,832	$ (323,061)	$ 55,945
Balance (in shares) at Jun. 30, 2018	15,744,645	(273,937)			15,744,645