Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity (Valuation Assumptions) (Details)

v3.21.1
Stockholders' Equity (Valuation Assumptions) (Details)
3 Months Ended
Mar. 26, 2021
Dec. 17, 2020
Dec. 07, 2020
Nov. 05, 2020
Apr. 06, 2020
Mar. 24, 2020
Mar. 31, 2021
Mar. 31, 2020
Stockholders' Equity [Abstract]                
Risk-free interest rate             1.01% 0.58%
Expected life (years)             6 years 6 years
Expected volatility 73.97% 77.41% 77.35% 77.36% 78.21% 77.56% 73.97% 77.57%