Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings (Accumulated Deficit) [Member]	Total
Balance at Dec. 31, 2018	$ 426	$ 115,719	$ (46,932)	$ 69,213
Balance (in shares) at Dec. 31, 2018	42,602,431
Issuance of common stock upon exercise of stock options		9		$ 9
Issuance of common stock upon exercise of stock options (in shares)	10,000			10,000
Issuance of common stock for services		10		$ 10
Issuance of common stock for services (in shares)	16,129
Value of share-based arrangements		1,819		1,819
Net loss			(25,940)	(25,940)
Balance at Dec. 31, 2019	$ 426	117,557	(72,872)	45,111
Balance (in shares) at Dec. 31, 2019	42,628,560
Issuance of common stock upon exercise of stock options	$ 7	56		$ 63
Issuance of common stock upon exercise of stock options (in shares)	683,613			1,967,562
Issuance of common stock for services		35		$ 35
Issuance of common stock for services (in shares)	35,714
Value of share-based arrangements		621		621
Net loss			(5,208)	(5,208)
Balance at Dec. 31, 2020	$ 433	$ 118,269	$ (78,080)	$ 40,622
Balance (in shares) at Dec. 31, 2020	43,347,887