Quarterly report pursuant to Section 13 or 15(d)

Organization and Summary of Significant Accounting Policies - Additional Information (Details)

v3.19.3
Organization and Summary of Significant Accounting Policies - Additional Information (Details)
$ / shares in Units, $ in Thousands
1 Months Ended 3 Months Ended 9 Months Ended
Oct. 31, 2019
USD ($)
shares
Jan. 31, 2019
$ / shares
Sep. 30, 2019
USD ($)
segment
$ / shares
shares
Sep. 30, 2018
USD ($)
shares
Sep. 30, 2019
USD ($)
$ / shares
Sep. 30, 2018
USD ($)
segment
Dec. 31, 2018
USD ($)
$ / shares
Schedule of Organization and Summary of Significant Accounting Policies              
Number of Operating Segments | segment     1     1  
Stockholders' Equity Note, Stock Split, Conversion Ratio   0.1667          
Substantial Doubt about Going Concern, Management's Evaluation         Going concern assessmentWe assess going concern uncertainty in our condensed financial statements to determine if we have sufficient cash on hand and working capital, including available borrowings on loans, to operate for a period of at least one year from the date the financial statements are issued or available to be issued, which is referred to as the "look-forward period" as defined by Accounting Standard Update ("ASU") No. 2014-15. As part of this assessment, based on conditions that are known and reasonably knowable to us, we will consider various scenarios, forecasts, projections, estimates and will make certain key assumptions, including the timing and nature of projected cash expenditures or programs, and its ability to delay or curtail expenditures or programs, if necessary, among other factors. Based on this assessment, as necessary or applicable, we make certain assumptions around implementing curtailments or delays in the nature and timing of programs and expenditures to the extent we deem probable those implementations can be achieved and we have the proper authority to execute them within the look-forward period in accordance with ASU No. 2014-15.Based upon the above assessment, we concluded that at the date of filing the financial statements in this Quarterly Report on Form 10-Q for the nine months ended September 30, 2019, we did not have sufficient cash to fund our operations for the next 12 months without additional funds and, therefore, there is substantial doubt about our ability to continue as a going concern within 12 months after the date the financial statements were issued.    
Cash and Cash Equivalents, at Carrying Value | $     $ 921 $ 8,427 $ 921 $ 8,427 $ 9,295
Common Stock, Par or Stated Value Per Share | $ / shares   $ 0.001 $ 0.001   $ 0.001   $ 0.001
Proceeds from sale of common stock | $         $ 2,467 $ 8,459  
Accounting Standards Update 2016-02 [Member]              
Schedule of Organization and Summary of Significant Accounting Policies              
Lessee, Operating Lease, Discount Rate   12.00%          
Fair Value, Recurring [Member] | Money Market Funds [Member]              
Schedule of Organization and Summary of Significant Accounting Policies              
Cash Equivalents, at Carrying Value | $     $ 800   $ 800   $ 8,900
Common Stock [Member]              
Schedule of Organization and Summary of Significant Accounting Policies              
Sale of common stock | shares     1,480,000 850,000      
October 2019 Equity Offering | Subsequent Event              
Schedule of Organization and Summary of Significant Accounting Policies              
Sale of common stock | shares 40,276,000            
October 2019 Equity Offering | Common Stock [Member] | Subsequent Event              
Schedule of Organization and Summary of Significant Accounting Policies              
Proceeds from sale of common stock | $ $ 9,100            
Sale of common stock | shares 35,886,000            
October 2019 Equity Offering | Common Stock [Member] | Placement Warrants [Member] | Subsequent Event              
Schedule of Organization and Summary of Significant Accounting Policies              
Class of Warrant or Right, Number of Securities Called by Warrants or Rights | shares 40,276,000