Quarterly report pursuant to Section 13 or 15(d)

Organization and Description of Business Operations (Details Textual)

v3.8.0.1
Organization and Description of Business Operations (Details Textual) - USD ($)
$ / shares in Units, $ in Thousands
1 Months Ended 3 Months Ended
Mar. 31, 2018
Mar. 31, 2018
Mar. 31, 2017
Dec. 31, 2017
Retained Earnings (Accumulated Deficit) $ (67,795) $ (67,795)   $ (59,030)
Payments of Stock Issuance Costs   $ 2,167 $ 0  
Underwritten Public Offering [Member]        
Stock Issued During Period, Shares, New Issues 5,290,000      
Shares Issued, Price Per Share $ 4.35 $ 4.35    
Stock Issued During Period, Value, New Issues $ 23,000      
Proceeds from Issuance Underwritten Public Offering 20,800      
Payments of Stock Issuance Costs $ 2,200