General form of registration statement for all companies including face-amount certificate companies

Stock-Based Compensation - Stock option awards granted to employees was estimated at the date of grant using the Black-Scholes option-pricing (Details)

v3.22.2
Stock-Based Compensation - Stock option awards granted to employees was estimated at the date of grant using the Black-Scholes option-pricing (Details)
 3 Months Ended 12 Months Ended
Mar. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Fair value of common stock 5.95%      
Maximum [Member]        
Fair value of common stock   8.56% 4.15% 3.84%
Expected term (years) 6 years 1 month 6 days 6 years 3 months 10 days 6 years 1 month 9 days 6 years 1 month 9 days
Volatility 75.19% 75.19% 74.34% 59.39%
Risk-free rate 0.69% 1.21% 1.66% 1.98%
Minimum [Member]        
Fair value of common stock   5.95% 3.48% 3.41%
Expected term (years) 5 years 5 years 5 years 5 years
Volatility 73.66% 62.33% 61.12% 58.49%
Risk-free rate 0.50% 0.50% 0.21% 1.72%