Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid In Capital	Accumulated Deficit
Beginning Balance (in shares) at Dec. 31, 2017		2,535,766
Beginning Balance at Dec. 31, 2017	$ 13,000	$ 2	$ 66,223	$ (53,225)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of warrants (in shares)		2,400
Exercise of warrants	24		24
Issuance of common stock for cash, net of issuance costs (in shares)		48,634
Issuance of common stock, net of issuance costs	642	$ 0	641
Stock based compensation from issuance of stock options	1,609		1,609
Net loss	(9,344)			(9,344)
Ending Balance (in shares) at Mar. 31, 2018		2,586,800
Ending Balance at Mar. 31, 2018	5,931	$ 3	68,497	(62,569)
Beginning Balance (in shares) at Dec. 31, 2018		3,845,361
Beginning Balance at Dec. 31, 2018	16,859	$ 4	91,276	(74,421)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)		80,000
Exercise of stock options	601		601
Issuance of common stock for cash, net of issuance costs (in shares)		80,000
Stock based compensation from issuance of stock options	1,066		1,066
Net loss	(1,736)			(1,736)
Ending Balance (in shares) at Mar. 31, 2019		3,925,361
Ending Balance at Mar. 31, 2019	$ 16,790	$ 4	$ 92,943	$ (76,157)