Consolidated Statement of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Series A Preferred Stock	Series A-1 Preferred Stock	Common Stock	Additional Paid-In Capital	Additional Paid-In Capital Series A Preferred Stock	Additional Paid-In Capital Series A-1 Preferred Stock	Retained Earnings / (Accumulated Deficit)
Balance, beginning amount at Dec. 31, 2014	$ 18,124			$ 2	$ 23,126			$ (5,004)
Balance, beginning shares at Dec. 31, 2014				22,448,098
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation expense	766				766
Proceeds from exercise of stock options	54				54
Proceeds from exercise of stock options, shares				192,513
Accretion of preferred stock		$ 0	$ 0
Net Income (Loss)	(12,602)							(12,602)
Balance, ending amount at Dec. 31, 2015	6,342			$ 2	23,946			(17,606)
Balance, ending shares at Dec. 31, 2015				22,640,611
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation expense	872				872
Proceeds from exercise of stock options	$ 111				111
Proceeds from exercise of stock options, shares	67,000			462,117
Accretion of preferred stock		(6,789)	0			$ (6,789)
Net Income (Loss)	$ 350							350
Balance, ending amount at Dec. 31, 2016	886			$ 2	18,140			(17,256)
Balance, ending shares at Dec. 31, 2016				23,102,728
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation expense	843				843
Proceeds from exercise of stock options	$ 229				229
Proceeds from exercise of stock options, shares	141,840			464,600
Accretion of preferred stock		$ (292)	$ (4,590)			$ (292)	$ (4,590)
Issuance of warrants classified as a liability	$ (3,313)				(3,313)
Sale of Common Stock	11,952			$ 1	11,951
Sale of Common Stock (shares)				4,140,000
Net Income (Loss)	22,811							22,811
Balance, ending amount at Dec. 31, 2017	$ 28,526			$ 3	$ 22,968			$ 5,555
Balance, ending shares at Dec. 31, 2017				27,707,328