Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies - Net Loss per Share - Basic and Diluted (Details)

v3.19.2
Summary of Significant Accounting Policies - Net Loss per Share - Basic and Diluted (Details) - shares
 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Total Shares of Potential Common Stock Equivalents 56,309,002 57,148,871
Common Stock    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Total Shares of Potential Common Stock Equivalents 40,744,086 42,255,336
Preferred Stock [Member]    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Total Shares of Potential Common Stock Equivalents 12,787,500 12,787,500
Employee Stock Option    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Total Shares of Potential Common Stock Equivalents 2,777,416 2,106,035