Statements of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid- in- Capital	Accumulated Deficit
Balances at Dec. 31, 2016	$ (380)	$ 1	$ 11,243	$ (11,624)
Balance (in shares) at Dec. 31, 2016		7,463,000
Common stock issued	10,430		10,430
Common stock issued, Shares		421,000
Common stock issued for services	100	$ 0	100
Common stock issued for services, Shares		4,000
Net loss	(17,765)			(17,765)
Balances at Dec. 31, 2017	(7,615)	$ 1	21,773	(29,389)
Balance (in shares) at Dec. 31, 2017		7,888,000
Common stock issued	78,806		78,806
Common stock issued, Shares		4,801,000
Initial Public Offering Costs	(3,556)		(3,556)
Settlement of stock-based compensation liability	18,243		18,243
Forfeitures of liability-classified awards	1,313		1,313
Stock-based compensation	10,346		10,346
Net loss	(30,832)			(30,832)
Balances at Dec. 31, 2018	$ 66,705	$ 1	$ 126,925	$ (60,221)
Balance (in shares) at Dec. 31, 2018		12,689,000