Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation - Fair Value Assumptions of Stock Option Granted (Details)

v3.22.1
Stock-Based Compensation - Fair Value Assumptions of Stock Option Granted (Details) - Stock options - 2014 Plan
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Dividend yield 0.00% 0.00%
Minimum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Risk-free interest rate 0.01% 0.28%
Expected term (years) 5 years 3 months 7 days 5 years 7 months 24 days
Volatility 119.10% 92.51%
Maximum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Risk-free interest rate 1.11% 0.46%
Expected term (years) 6 years 1 month 17 days 6 years 1 month 17 days
Volatility 138.00% 107.87%