XML 59 R48.htm IDEA: XBRL DOCUMENT v3.21.2
Share-Based Compensation - Grant-date Fair Value of Options Granted (Details) - Options
6 Months Ended
Jun. 30, 2021
$ / shares
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]  
Risk-free interest rate 0.59%
Expected term (in years) 6 years
Expected volatility 97.20%
Fair value per share of underlying stock $ 3.91
Weighted average grant date fair value of the options granted $ 3.01